1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1988, 1993
5 * The Regents of the University of California.
6 * 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 * $FreeBSD$
34 */
35
36 #ifndef _SYS_MBUF_H_
37 #define _SYS_MBUF_H_
38
39 /* XXX: These includes suck. Sorry! */
40 #include <sys/queue.h>
41 #ifdef _KERNEL
42 #include <sys/systm.h>
43 #include <vm/uma.h>
44 #ifdef WITNESS
45 #include <sys/lock.h>
46 #endif
47 #endif
48
49 #ifdef _KERNEL
50 #include <sys/sdt.h>
51
52 #define MBUF_PROBE1(probe, arg0) \
53 SDT_PROBE1(sdt, , , probe, arg0)
54 #define MBUF_PROBE2(probe, arg0, arg1) \
55 SDT_PROBE2(sdt, , , probe, arg0, arg1)
56 #define MBUF_PROBE3(probe, arg0, arg1, arg2) \
57 SDT_PROBE3(sdt, , , probe, arg0, arg1, arg2)
58 #define MBUF_PROBE4(probe, arg0, arg1, arg2, arg3) \
59 SDT_PROBE4(sdt, , , probe, arg0, arg1, arg2, arg3)
60 #define MBUF_PROBE5(probe, arg0, arg1, arg2, arg3, arg4) \
61 SDT_PROBE5(sdt, , , probe, arg0, arg1, arg2, arg3, arg4)
62
63 SDT_PROBE_DECLARE(sdt, , , m__init);
64 SDT_PROBE_DECLARE(sdt, , , m__gethdr);
65 SDT_PROBE_DECLARE(sdt, , , m__get);
66 SDT_PROBE_DECLARE(sdt, , , m__getcl);
67 SDT_PROBE_DECLARE(sdt, , , m__clget);
68 SDT_PROBE_DECLARE(sdt, , , m__cljget);
69 SDT_PROBE_DECLARE(sdt, , , m__cljset);
70 SDT_PROBE_DECLARE(sdt, , , m__free);
71 SDT_PROBE_DECLARE(sdt, , , m__freem);
72
73 #endif /* _KERNEL */
74
75 /*
76 * Mbufs are of a single size, MSIZE (sys/param.h), which includes overhead.
77 * An mbuf may add a single "mbuf cluster" of size MCLBYTES (also in
78 * sys/param.h), which has no additional overhead and is used instead of the
79 * internal data area; this is done when at least MINCLSIZE of data must be
80 * stored. Additionally, it is possible to allocate a separate buffer
81 * externally and attach it to the mbuf in a way similar to that of mbuf
82 * clusters.
83 *
84 * NB: These calculation do not take actual compiler-induced alignment and
85 * padding inside the complete struct mbuf into account. Appropriate
86 * attention is required when changing members of struct mbuf.
87 *
88 * MLEN is data length in a normal mbuf.
89 * MHLEN is data length in an mbuf with pktheader.
90 * MINCLSIZE is a smallest amount of data that should be put into cluster.
91 *
92 * Compile-time assertions in uipc_mbuf.c test these values to ensure that
93 * they are sensible.
94 */
95 struct mbuf;
96 #define MHSIZE offsetof(struct mbuf, m_dat)
97 #define MPKTHSIZE offsetof(struct mbuf, m_pktdat)
98 #define MLEN ((int)(MSIZE - MHSIZE))
99 #define MHLEN ((int)(MSIZE - MPKTHSIZE))
100 #define MINCLSIZE (MHLEN + 1)
101
102 #ifdef _KERNEL
103 /*-
104 * Macro for type conversion: convert mbuf pointer to data pointer of correct
105 * type:
106 *
107 * mtod(m, t) -- Convert mbuf pointer to data pointer of correct type.
108 * mtodo(m, o) -- Same as above but with offset 'o' into data.
109 */
110 #define mtod(m, t) ((t)((m)->m_data))
111 #define mtodo(m, o) ((void *)(((m)->m_data) + (o)))
112
113 /*
114 * Argument structure passed to UMA routines during mbuf and packet
115 * allocations.
116 */
117 struct mb_args {
118 int flags; /* Flags for mbuf being allocated */
119 short type; /* Type of mbuf being allocated */
120 };
121 #endif /* _KERNEL */
122
123 /*
124 * Packet tag structure (see below for details).
125 */
126 struct m_tag {
127 SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */
128 u_int16_t m_tag_id; /* Tag ID */
129 u_int16_t m_tag_len; /* Length of data */
130 u_int32_t m_tag_cookie; /* ABI/Module ID */
131 void (*m_tag_free)(struct m_tag *);
132 };
133
134 /*
135 * Static network interface owned tag.
136 * Allocated through ifp->if_snd_tag_alloc().
137 */
138 struct m_snd_tag {
139 struct ifnet *ifp; /* network interface tag belongs to */
140 };
141
142 /*
143 * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set.
144 * Size ILP32: 48
145 * LP64: 56
146 * Compile-time assertions in uipc_mbuf.c test these values to ensure that
147 * they are correct.
148 */
149 struct pkthdr {
150 union {
151 struct m_snd_tag *snd_tag; /* send tag, if any */
152 struct ifnet *rcvif; /* rcv interface */
153 };
154 SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */
155 int32_t len; /* total packet length */
156
157 /* Layer crossing persistent information. */
158 uint32_t flowid; /* packet's 4-tuple system */
159 uint32_t csum_flags; /* checksum and offload features */
160 uint16_t fibnum; /* this packet should use this fib */
161 uint8_t cosqos; /* class/quality of service */
162 uint8_t rsstype; /* hash type */
163 union {
164 uint64_t rcv_tstmp; /* timestamp in ns */
165 struct {
166 uint8_t l2hlen; /* layer 2 hdr len */
167 uint8_t l3hlen; /* layer 3 hdr len */
168 uint8_t l4hlen; /* layer 4 hdr len */
169 uint8_t l5hlen; /* layer 5 hdr len */
170 uint32_t spare;
171 };
172 };
173 union {
174 uint8_t eight[8];
175 uint16_t sixteen[4];
176 uint32_t thirtytwo[2];
177 uint64_t sixtyfour[1];
178 uintptr_t unintptr[1];
179 void *ptr;
180 } PH_per;
181
182 /* Layer specific non-persistent local storage for reassembly, etc. */
183 union {
184 uint8_t eight[8];
185 uint16_t sixteen[4];
186 uint32_t thirtytwo[2];
187 uint64_t sixtyfour[1];
188 uintptr_t unintptr[1];
189 void *ptr;
190 } PH_loc;
191 };
192 #define ether_vtag PH_per.sixteen[0]
193 #define PH_vt PH_per
194 #define vt_nrecs sixteen[0]
195 #define tso_segsz PH_per.sixteen[1]
196 #define lro_nsegs tso_segsz
197 #define csum_phsum PH_per.sixteen[2]
198 #define csum_data PH_per.thirtytwo[1]
199 #define pace_thoff PH_loc.sixteen[0]
200 #define pace_tlen PH_loc.sixteen[1]
201 #define pace_drphdrlen PH_loc.sixteen[2]
202 #define pace_tos PH_loc.eight[6]
203 #define pace_lock PH_loc.eight[7]
204
205 /*
206 * Description of external storage mapped into mbuf; valid only if M_EXT is
207 * set.
208 * Size ILP32: 28
209 * LP64: 48
210 * Compile-time assertions in uipc_mbuf.c test these values to ensure that
211 * they are correct.
212 */
213 typedef void m_ext_free_t(struct mbuf *);
214 struct m_ext {
215 union {
216 /*
217 * If EXT_FLAG_EMBREF is set, then we use refcount in the
218 * mbuf, the 'ext_count' member. Otherwise, we have a
219 * shadow copy and we use pointer 'ext_cnt'. The original
220 * mbuf is responsible to carry the pointer to free routine
221 * and its arguments. They aren't copied into shadows in
222 * mb_dupcl() to avoid dereferencing next cachelines.
223 */
224 volatile u_int ext_count;
225 volatile u_int *ext_cnt;
226 };
227 char *ext_buf; /* start of buffer */
228 uint32_t ext_size; /* size of buffer, for ext_free */
229 uint32_t ext_type:8, /* type of external storage */
230 ext_flags:24; /* external storage mbuf flags */
231 /*
232 * Fields below store the free context for the external storage.
233 * They are valid only in the refcount carrying mbuf, the one with
234 * EXT_FLAG_EMBREF flag, with exclusion for EXT_EXTREF type, where
235 * the free context is copied into all mbufs that use same external
236 * storage.
237 */
238 #define m_ext_copylen offsetof(struct m_ext, ext_free)
239 m_ext_free_t *ext_free; /* free routine if not the usual */
240 void *ext_arg1; /* optional argument pointer */
241 void *ext_arg2; /* optional argument pointer */
242 };
243
244 /*
245 * The core of the mbuf object along with some shortcut defines for practical
246 * purposes.
247 */
248 struct mbuf {
249 /*
250 * Header present at the beginning of every mbuf.
251 * Size ILP32: 24
252 * LP64: 32
253 * Compile-time assertions in uipc_mbuf.c test these values to ensure
254 * that they are correct.
255 */
256 union { /* next buffer in chain */
257 struct mbuf *m_next;
258 SLIST_ENTRY(mbuf) m_slist;
259 STAILQ_ENTRY(mbuf) m_stailq;
260 };
261 union { /* next chain in queue/record */
262 struct mbuf *m_nextpkt;
263 SLIST_ENTRY(mbuf) m_slistpkt;
264 STAILQ_ENTRY(mbuf) m_stailqpkt;
265 };
266 caddr_t m_data; /* location of data */
267 int32_t m_len; /* amount of data in this mbuf */
268 uint32_t m_type:8, /* type of data in this mbuf */
269 m_flags:24; /* flags; see below */
270 #if !defined(__LP64__)
271 uint32_t m_pad; /* pad for 64bit alignment */
272 #endif
273
274 /*
275 * A set of optional headers (packet header, external storage header)
276 * and internal data storage. Historically, these arrays were sized
277 * to MHLEN (space left after a packet header) and MLEN (space left
278 * after only a regular mbuf header); they are now variable size in
279 * order to support future work on variable-size mbufs.
280 */
281 union {
282 struct {
283 struct pkthdr m_pkthdr; /* M_PKTHDR set */
284 union {
285 struct m_ext m_ext; /* M_EXT set */
286 char m_pktdat[0];
287 };
288 };
289 char m_dat[0]; /* !M_PKTHDR, !M_EXT */
290 };
291 };
292
293 /*
294 * mbuf flags of global significance and layer crossing.
295 * Those of only protocol/layer specific significance are to be mapped
296 * to M_PROTO[1-12] and cleared at layer handoff boundaries.
297 * NB: Limited to the lower 24 bits.
298 */
299 #define M_EXT 0x00000001 /* has associated external storage */
300 #define M_PKTHDR 0x00000002 /* start of record */
301 #define M_EOR 0x00000004 /* end of record */
302 #define M_RDONLY 0x00000008 /* associated data is marked read-only */
303 #define M_BCAST 0x00000010 /* send/received as link-level broadcast */
304 #define M_MCAST 0x00000020 /* send/received as link-level multicast */
305 #define M_PROMISC 0x00000040 /* packet was not for us */
306 #define M_VLANTAG 0x00000080 /* ether_vtag is valid */
307 #define M_NOMAP 0x00000100 /* mbuf data is unmapped (soon from Drew) */
308 #define M_NOFREE 0x00000200 /* do not free mbuf, embedded in cluster */
309 #define M_TSTMP 0x00000400 /* rcv_tstmp field is valid */
310 #define M_TSTMP_HPREC 0x00000800 /* rcv_tstmp is high-prec, typically
311 hw-stamped on port (useful for IEEE 1588
312 and 802.1AS) */
313
314 #define M_PROTO1 0x00001000 /* protocol-specific */
315 #define M_PROTO2 0x00002000 /* protocol-specific */
316 #define M_PROTO3 0x00004000 /* protocol-specific */
317 #define M_PROTO4 0x00008000 /* protocol-specific */
318 #define M_PROTO5 0x00010000 /* protocol-specific */
319 #define M_PROTO6 0x00020000 /* protocol-specific */
320 #define M_PROTO7 0x00040000 /* protocol-specific */
321 #define M_PROTO8 0x00080000 /* protocol-specific */
322 #define M_PROTO9 0x00100000 /* protocol-specific */
323 #define M_PROTO10 0x00200000 /* protocol-specific */
324 #define M_PROTO11 0x00400000 /* protocol-specific */
325 #define M_PROTO12 0x00800000 /* protocol-specific */
326
327 #define MB_DTOR_SKIP 0x1 /* don't pollute the cache by touching a freed mbuf */
328
329 /*
330 * Flags to purge when crossing layers.
331 */
332 #define M_PROTOFLAGS \
333 (M_PROTO1|M_PROTO2|M_PROTO3|M_PROTO4|M_PROTO5|M_PROTO6|M_PROTO7|M_PROTO8|\
334 M_PROTO9|M_PROTO10|M_PROTO11|M_PROTO12)
335
336 /*
337 * Flags preserved when copying m_pkthdr.
338 */
339 #define M_COPYFLAGS \
340 (M_PKTHDR|M_EOR|M_RDONLY|M_BCAST|M_MCAST|M_PROMISC|M_VLANTAG|M_TSTMP| \
341 M_TSTMP_HPREC|M_PROTOFLAGS)
342
343 /*
344 * Mbuf flag description for use with printf(9) %b identifier.
345 */
346 #define M_FLAG_BITS \
347 "\20\1M_EXT\2M_PKTHDR\3M_EOR\4M_RDONLY\5M_BCAST\6M_MCAST" \
348 "\7M_PROMISC\10M_VLANTAG\13M_TSTMP\14M_TSTMP_HPREC"
349 #define M_FLAG_PROTOBITS \
350 "\15M_PROTO1\16M_PROTO2\17M_PROTO3\20M_PROTO4\21M_PROTO5" \
351 "\22M_PROTO6\23M_PROTO7\24M_PROTO8\25M_PROTO9\26M_PROTO10" \
352 "\27M_PROTO11\30M_PROTO12"
353 #define M_FLAG_PRINTF (M_FLAG_BITS M_FLAG_PROTOBITS)
354
355 /*
356 * Network interface cards are able to hash protocol fields (such as IPv4
357 * addresses and TCP port numbers) classify packets into flows. These flows
358 * can then be used to maintain ordering while delivering packets to the OS
359 * via parallel input queues, as well as to provide a stateless affinity
360 * model. NIC drivers can pass up the hash via m->m_pkthdr.flowid, and set
361 * m_flag fields to indicate how the hash should be interpreted by the
362 * network stack.
363 *
364 * Most NICs support RSS, which provides ordering and explicit affinity, and
365 * use the hash m_flag bits to indicate what header fields were covered by
366 * the hash. M_HASHTYPE_OPAQUE and M_HASHTYPE_OPAQUE_HASH can be set by non-
367 * RSS cards or configurations that provide an opaque flow identifier, allowing
368 * for ordering and distribution without explicit affinity. Additionally,
369 * M_HASHTYPE_OPAQUE_HASH indicates that the flow identifier has hash
370 * properties.
371 *
372 * The meaning of the IPV6_EX suffix:
373 * "o Home address from the home address option in the IPv6 destination
374 * options header. If the extension header is not present, use the Source
375 * IPv6 Address.
376 * o IPv6 address that is contained in the Routing-Header-Type-2 from the
377 * associated extension header. If the extension header is not present,
378 * use the Destination IPv6 Address."
379 * Quoted from:
380 * https://docs.microsoft.com/en-us/windows-hardware/drivers/network/rss-hashing-types#ndishashipv6ex
381 */
382 #define M_HASHTYPE_HASHPROP 0x80 /* has hash properties */
383 #define M_HASHTYPE_HASH(t) (M_HASHTYPE_HASHPROP | (t))
384 /* Microsoft RSS standard hash types */
385 #define M_HASHTYPE_NONE 0
386 #define M_HASHTYPE_RSS_IPV4 M_HASHTYPE_HASH(1) /* IPv4 2-tuple */
387 #define M_HASHTYPE_RSS_TCP_IPV4 M_HASHTYPE_HASH(2) /* TCPv4 4-tuple */
388 #define M_HASHTYPE_RSS_IPV6 M_HASHTYPE_HASH(3) /* IPv6 2-tuple */
389 #define M_HASHTYPE_RSS_TCP_IPV6 M_HASHTYPE_HASH(4) /* TCPv6 4-tuple */
390 #define M_HASHTYPE_RSS_IPV6_EX M_HASHTYPE_HASH(5) /* IPv6 2-tuple +
391 * ext hdrs */
392 #define M_HASHTYPE_RSS_TCP_IPV6_EX M_HASHTYPE_HASH(6) /* TCPv6 4-tuple +
393 * ext hdrs */
394 #define M_HASHTYPE_RSS_UDP_IPV4 M_HASHTYPE_HASH(7) /* IPv4 UDP 4-tuple*/
395 #define M_HASHTYPE_RSS_UDP_IPV6 M_HASHTYPE_HASH(9) /* IPv6 UDP 4-tuple*/
396 #define M_HASHTYPE_RSS_UDP_IPV6_EX M_HASHTYPE_HASH(10)/* IPv6 UDP 4-tuple +
397 * ext hdrs */
398
399 #define M_HASHTYPE_OPAQUE 63 /* ordering, not affinity */
400 #define M_HASHTYPE_OPAQUE_HASH M_HASHTYPE_HASH(M_HASHTYPE_OPAQUE)
401 /* ordering+hash, not affinity*/
402
403 #define M_HASHTYPE_CLEAR(m) ((m)->m_pkthdr.rsstype = 0)
404 #define M_HASHTYPE_GET(m) ((m)->m_pkthdr.rsstype)
405 #define M_HASHTYPE_SET(m, v) ((m)->m_pkthdr.rsstype = (v))
406 #define M_HASHTYPE_TEST(m, v) (M_HASHTYPE_GET(m) == (v))
407 #define M_HASHTYPE_ISHASH(m) (M_HASHTYPE_GET(m) & M_HASHTYPE_HASHPROP)
408
409 /*
410 * COS/QOS class and quality of service tags.
411 * It uses DSCP code points as base.
412 */
413 #define QOS_DSCP_CS0 0x00
414 #define QOS_DSCP_DEF QOS_DSCP_CS0
415 #define QOS_DSCP_CS1 0x20
416 #define QOS_DSCP_AF11 0x28
417 #define QOS_DSCP_AF12 0x30
418 #define QOS_DSCP_AF13 0x38
419 #define QOS_DSCP_CS2 0x40
420 #define QOS_DSCP_AF21 0x48
421 #define QOS_DSCP_AF22 0x50
422 #define QOS_DSCP_AF23 0x58
423 #define QOS_DSCP_CS3 0x60
424 #define QOS_DSCP_AF31 0x68
425 #define QOS_DSCP_AF32 0x70
426 #define QOS_DSCP_AF33 0x78
427 #define QOS_DSCP_CS4 0x80
428 #define QOS_DSCP_AF41 0x88
429 #define QOS_DSCP_AF42 0x90
430 #define QOS_DSCP_AF43 0x98
431 #define QOS_DSCP_CS5 0xa0
432 #define QOS_DSCP_EF 0xb8
433 #define QOS_DSCP_CS6 0xc0
434 #define QOS_DSCP_CS7 0xe0
435
436 /*
437 * External mbuf storage buffer types.
438 */
439 #define EXT_CLUSTER 1 /* mbuf cluster */
440 #define EXT_SFBUF 2 /* sendfile(2)'s sf_buf */
441 #define EXT_JUMBOP 3 /* jumbo cluster page sized */
442 #define EXT_JUMBO9 4 /* jumbo cluster 9216 bytes */
443 #define EXT_JUMBO16 5 /* jumbo cluster 16184 bytes */
444 #define EXT_PACKET 6 /* mbuf+cluster from packet zone */
445 #define EXT_MBUF 7 /* external mbuf reference */
446
447 #define EXT_VENDOR1 224 /* for vendor-internal use */
448 #define EXT_VENDOR2 225 /* for vendor-internal use */
449 #define EXT_VENDOR3 226 /* for vendor-internal use */
450 #define EXT_VENDOR4 227 /* for vendor-internal use */
451
452 #define EXT_EXP1 244 /* for experimental use */
453 #define EXT_EXP2 245 /* for experimental use */
454 #define EXT_EXP3 246 /* for experimental use */
455 #define EXT_EXP4 247 /* for experimental use */
456
457 #define EXT_NET_DRV 252 /* custom ext_buf provided by net driver(s) */
458 #define EXT_MOD_TYPE 253 /* custom module's ext_buf type */
459 #define EXT_DISPOSABLE 254 /* can throw this buffer away w/page flipping */
460 #define EXT_EXTREF 255 /* has externally maintained ext_cnt ptr */
461
462 /*
463 * Flags for external mbuf buffer types.
464 * NB: limited to the lower 24 bits.
465 */
466 #define EXT_FLAG_EMBREF 0x000001 /* embedded ext_count */
467 #define EXT_FLAG_EXTREF 0x000002 /* external ext_cnt, notyet */
468
469 #define EXT_FLAG_NOFREE 0x000010 /* don't free mbuf to pool, notyet */
470
471 #define EXT_FLAG_VENDOR1 0x010000 /* These flags are vendor */
472 #define EXT_FLAG_VENDOR2 0x020000 /* or submodule specific, */
473 #define EXT_FLAG_VENDOR3 0x040000 /* not used by mbuf code. */
474 #define EXT_FLAG_VENDOR4 0x080000 /* Set/read by submodule. */
475
476 #define EXT_FLAG_EXP1 0x100000 /* for experimental use */
477 #define EXT_FLAG_EXP2 0x200000 /* for experimental use */
478 #define EXT_FLAG_EXP3 0x400000 /* for experimental use */
479 #define EXT_FLAG_EXP4 0x800000 /* for experimental use */
480
481 /*
482 * EXT flag description for use with printf(9) %b identifier.
483 */
484 #define EXT_FLAG_BITS \
485 "\20\1EXT_FLAG_EMBREF\2EXT_FLAG_EXTREF\5EXT_FLAG_NOFREE" \
486 "\21EXT_FLAG_VENDOR1\22EXT_FLAG_VENDOR2\23EXT_FLAG_VENDOR3" \
487 "\24EXT_FLAG_VENDOR4\25EXT_FLAG_EXP1\26EXT_FLAG_EXP2\27EXT_FLAG_EXP3" \
488 "\30EXT_FLAG_EXP4"
489
490 /*
491 * Flags indicating checksum, segmentation and other offload work to be
492 * done, or already done, by hardware or lower layers. It is split into
493 * separate inbound and outbound flags.
494 *
495 * Outbound flags that are set by upper protocol layers requesting lower
496 * layers, or ideally the hardware, to perform these offloading tasks.
497 * For outbound packets this field and its flags can be directly tested
498 * against ifnet if_hwassist.
499 */
500 #define CSUM_IP 0x00000001 /* IP header checksum offload */
501 #define CSUM_IP_UDP 0x00000002 /* UDP checksum offload */
502 #define CSUM_IP_TCP 0x00000004 /* TCP checksum offload */
503 #define CSUM_IP_SCTP 0x00000008 /* SCTP checksum offload */
504 #define CSUM_IP_TSO 0x00000010 /* TCP segmentation offload */
505 #define CSUM_IP_ISCSI 0x00000020 /* iSCSI checksum offload */
506
507 #define CSUM_IP6_UDP 0x00000200 /* UDP checksum offload */
508 #define CSUM_IP6_TCP 0x00000400 /* TCP checksum offload */
509 #define CSUM_IP6_SCTP 0x00000800 /* SCTP checksum offload */
510 #define CSUM_IP6_TSO 0x00001000 /* TCP segmentation offload */
511 #define CSUM_IP6_ISCSI 0x00002000 /* iSCSI checksum offload */
512
513 /* Inbound checksum support where the checksum was verified by hardware. */
514 #define CSUM_L3_CALC 0x01000000 /* calculated layer 3 csum */
515 #define CSUM_L3_VALID 0x02000000 /* checksum is correct */
516 #define CSUM_L4_CALC 0x04000000 /* calculated layer 4 csum */
517 #define CSUM_L4_VALID 0x08000000 /* checksum is correct */
518 #define CSUM_L5_CALC 0x10000000 /* calculated layer 5 csum */
519 #define CSUM_L5_VALID 0x20000000 /* checksum is correct */
520 #define CSUM_COALESCED 0x40000000 /* contains merged segments */
521
522 #define CSUM_SND_TAG 0x80000000 /* Packet header has send tag */
523
524 /*
525 * CSUM flag description for use with printf(9) %b identifier.
526 */
527 #define CSUM_BITS \
528 "\20\1CSUM_IP\2CSUM_IP_UDP\3CSUM_IP_TCP\4CSUM_IP_SCTP\5CSUM_IP_TSO" \
529 "\6CSUM_IP_ISCSI" \
530 "\12CSUM_IP6_UDP\13CSUM_IP6_TCP\14CSUM_IP6_SCTP\15CSUM_IP6_TSO" \
531 "\16CSUM_IP6_ISCSI" \
532 "\31CSUM_L3_CALC\32CSUM_L3_VALID\33CSUM_L4_CALC\34CSUM_L4_VALID" \
533 "\35CSUM_L5_CALC\36CSUM_L5_VALID\37CSUM_COALESCED\40CSUM_SND_TAG"
534
535 /* CSUM flags compatibility mappings. */
536 #define CSUM_IP_CHECKED CSUM_L3_CALC
537 #define CSUM_IP_VALID CSUM_L3_VALID
538 #define CSUM_DATA_VALID CSUM_L4_VALID
539 #define CSUM_PSEUDO_HDR CSUM_L4_CALC
540 #define CSUM_SCTP_VALID CSUM_L4_VALID
541 #define CSUM_DELAY_DATA (CSUM_TCP|CSUM_UDP)
542 #define CSUM_DELAY_IP CSUM_IP /* Only v4, no v6 IP hdr csum */
543 #define CSUM_DELAY_DATA_IPV6 (CSUM_TCP_IPV6|CSUM_UDP_IPV6)
544 #define CSUM_DATA_VALID_IPV6 CSUM_DATA_VALID
545 #define CSUM_TCP CSUM_IP_TCP
546 #define CSUM_UDP CSUM_IP_UDP
547 #define CSUM_SCTP CSUM_IP_SCTP
548 #define CSUM_TSO (CSUM_IP_TSO|CSUM_IP6_TSO)
549 #define CSUM_UDP_IPV6 CSUM_IP6_UDP
550 #define CSUM_TCP_IPV6 CSUM_IP6_TCP
551 #define CSUM_SCTP_IPV6 CSUM_IP6_SCTP
552
553 /*
554 * mbuf types describing the content of the mbuf (including external storage).
555 */
556 #define MT_NOTMBUF 0 /* USED INTERNALLY ONLY! Object is not mbuf */
557 #define MT_DATA 1 /* dynamic (data) allocation */
558 #define MT_HEADER MT_DATA /* packet header, use M_PKTHDR instead */
559
560 #define MT_VENDOR1 4 /* for vendor-internal use */
561 #define MT_VENDOR2 5 /* for vendor-internal use */
562 #define MT_VENDOR3 6 /* for vendor-internal use */
563 #define MT_VENDOR4 7 /* for vendor-internal use */
564
565 #define MT_SONAME 8 /* socket name */
566
567 #define MT_EXP1 9 /* for experimental use */
568 #define MT_EXP2 10 /* for experimental use */
569 #define MT_EXP3 11 /* for experimental use */
570 #define MT_EXP4 12 /* for experimental use */
571
572 #define MT_CONTROL 14 /* extra-data protocol message */
573 #define MT_EXTCONTROL 15 /* control message with externalized contents */
574 #define MT_OOBDATA 16 /* expedited data */
575
576 #define MT_NOINIT 255 /* Not a type but a flag to allocate
577 a non-initialized mbuf */
578
579 /*
580 * String names of mbuf-related UMA(9) and malloc(9) types. Exposed to
581 * !_KERNEL so that monitoring tools can look up the zones with
582 * libmemstat(3).
583 */
584 #define MBUF_MEM_NAME "mbuf"
585 #define MBUF_CLUSTER_MEM_NAME "mbuf_cluster"
586 #define MBUF_PACKET_MEM_NAME "mbuf_packet"
587 #define MBUF_JUMBOP_MEM_NAME "mbuf_jumbo_page"
588 #define MBUF_JUMBO9_MEM_NAME "mbuf_jumbo_9k"
589 #define MBUF_JUMBO16_MEM_NAME "mbuf_jumbo_16k"
590 #define MBUF_TAG_MEM_NAME "mbuf_tag"
591 #define MBUF_EXTREFCNT_MEM_NAME "mbuf_ext_refcnt"
592
593 #ifdef _KERNEL
594
595 #ifdef WITNESS
596 #define MBUF_CHECKSLEEP(how) do { \
597 if (how == M_WAITOK) \
598 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, \
599 "Sleeping in \"%s\"", __func__); \
600 } while (0)
601 #else
602 #define MBUF_CHECKSLEEP(how)
603 #endif
604
605 /*
606 * Network buffer allocation API
607 *
608 * The rest of it is defined in kern/kern_mbuf.c
609 */
610 extern uma_zone_t zone_mbuf;
611 extern uma_zone_t zone_clust;
612 extern uma_zone_t zone_pack;
613 extern uma_zone_t zone_jumbop;
614 extern uma_zone_t zone_jumbo9;
615 extern uma_zone_t zone_jumbo16;
616
617 void mb_dupcl(struct mbuf *, struct mbuf *);
618 void mb_free_ext(struct mbuf *);
619 void m_adj(struct mbuf *, int);
620 int m_apply(struct mbuf *, int, int,
621 int (*)(void *, void *, u_int), void *);
622 int m_append(struct mbuf *, int, c_caddr_t);
623 void m_cat(struct mbuf *, struct mbuf *);
624 void m_catpkt(struct mbuf *, struct mbuf *);
625 int m_clget(struct mbuf *m, int how);
626 void *m_cljget(struct mbuf *m, int how, int size);
627 struct mbuf *m_collapse(struct mbuf *, int, int);
628 void m_copyback(struct mbuf *, int, int, c_caddr_t);
629 void m_copydata(const struct mbuf *, int, int, caddr_t);
630 struct mbuf *m_copym(struct mbuf *, int, int, int);
631 struct mbuf *m_copypacket(struct mbuf *, int);
632 void m_copy_pkthdr(struct mbuf *, struct mbuf *);
633 struct mbuf *m_copyup(struct mbuf *, int, int);
634 struct mbuf *m_defrag(struct mbuf *, int);
635 void m_demote_pkthdr(struct mbuf *);
636 void m_demote(struct mbuf *, int, int);
637 struct mbuf *m_devget(char *, int, int, struct ifnet *,
638 void (*)(char *, caddr_t, u_int));
639 void m_dispose_extcontrolm(struct mbuf *m);
640 struct mbuf *m_dup(const struct mbuf *, int);
641 int m_dup_pkthdr(struct mbuf *, const struct mbuf *, int);
642 void m_extadd(struct mbuf *, char *, u_int, m_ext_free_t,
643 void *, void *, int, int);
644 u_int m_fixhdr(struct mbuf *);
645 struct mbuf *m_fragment(struct mbuf *, int, int);
646 void m_freem(struct mbuf *);
647 struct mbuf *m_get2(int, int, short, int);
648 struct mbuf *m_getjcl(int, short, int, int);
649 struct mbuf *m_getm2(struct mbuf *, int, int, short, int);
650 struct mbuf *m_getptr(struct mbuf *, int, int *);
651 u_int m_length(struct mbuf *, struct mbuf **);
652 int m_mbuftouio(struct uio *, const struct mbuf *, int);
653 void m_move_pkthdr(struct mbuf *, struct mbuf *);
654 int m_pkthdr_init(struct mbuf *, int);
655 struct mbuf *m_prepend(struct mbuf *, int, int);
656 void m_print(const struct mbuf *, int);
657 struct mbuf *m_pulldown(struct mbuf *, int, int, int *);
658 struct mbuf *m_pullup(struct mbuf *, int);
659 int m_sanity(struct mbuf *, int);
660 struct mbuf *m_split(struct mbuf *, int, int);
661 struct mbuf *m_uiotombuf(struct uio *, int, int, int, int);
662 struct mbuf *m_unshare(struct mbuf *, int);
663
664 static __inline int
m_gettype(int size)665 m_gettype(int size)
666 {
667 int type;
668
669 switch (size) {
670 case MSIZE:
671 type = EXT_MBUF;
672 break;
673 case MCLBYTES:
674 type = EXT_CLUSTER;
675 break;
676 #if MJUMPAGESIZE != MCLBYTES
677 case MJUMPAGESIZE:
678 type = EXT_JUMBOP;
679 break;
680 #endif
681 case MJUM9BYTES:
682 type = EXT_JUMBO9;
683 break;
684 case MJUM16BYTES:
685 type = EXT_JUMBO16;
686 break;
687 default:
688 panic("%s: invalid cluster size %d", __func__, size);
689 }
690
691 return (type);
692 }
693
694 /*
695 * Associated an external reference counted buffer with an mbuf.
696 */
697 static __inline void
m_extaddref(struct mbuf * m,char * buf,u_int size,u_int * ref_cnt,m_ext_free_t freef,void * arg1,void * arg2)698 m_extaddref(struct mbuf *m, char *buf, u_int size, u_int *ref_cnt,
699 m_ext_free_t freef, void *arg1, void *arg2)
700 {
701
702 KASSERT(ref_cnt != NULL, ("%s: ref_cnt not provided", __func__));
703
704 atomic_add_int(ref_cnt, 1);
705 m->m_flags |= M_EXT;
706 m->m_ext.ext_buf = buf;
707 m->m_ext.ext_cnt = ref_cnt;
708 m->m_data = m->m_ext.ext_buf;
709 m->m_ext.ext_size = size;
710 m->m_ext.ext_free = freef;
711 m->m_ext.ext_arg1 = arg1;
712 m->m_ext.ext_arg2 = arg2;
713 m->m_ext.ext_type = EXT_EXTREF;
714 m->m_ext.ext_flags = 0;
715 }
716
717 static __inline uma_zone_t
m_getzone(int size)718 m_getzone(int size)
719 {
720 uma_zone_t zone;
721
722 switch (size) {
723 case MCLBYTES:
724 zone = zone_clust;
725 break;
726 #if MJUMPAGESIZE != MCLBYTES
727 case MJUMPAGESIZE:
728 zone = zone_jumbop;
729 break;
730 #endif
731 case MJUM9BYTES:
732 zone = zone_jumbo9;
733 break;
734 case MJUM16BYTES:
735 zone = zone_jumbo16;
736 break;
737 default:
738 panic("%s: invalid cluster size %d", __func__, size);
739 }
740
741 return (zone);
742 }
743
744 /*
745 * Initialize an mbuf with linear storage.
746 *
747 * Inline because the consumer text overhead will be roughly the same to
748 * initialize or call a function with this many parameters and M_PKTHDR
749 * should go away with constant propagation for !MGETHDR.
750 */
751 static __inline int
m_init(struct mbuf * m,int how,short type,int flags)752 m_init(struct mbuf *m, int how, short type, int flags)
753 {
754 int error;
755
756 m->m_next = NULL;
757 m->m_nextpkt = NULL;
758 m->m_data = m->m_dat;
759 m->m_len = 0;
760 m->m_flags = flags;
761 m->m_type = type;
762 if (flags & M_PKTHDR)
763 error = m_pkthdr_init(m, how);
764 else
765 error = 0;
766
767 MBUF_PROBE5(m__init, m, how, type, flags, error);
768 return (error);
769 }
770
771 static __inline struct mbuf *
m_get(int how,short type)772 m_get(int how, short type)
773 {
774 struct mbuf *m;
775 struct mb_args args;
776
777 args.flags = 0;
778 args.type = type;
779 m = uma_zalloc_arg(zone_mbuf, &args, how);
780 MBUF_PROBE3(m__get, how, type, m);
781 return (m);
782 }
783
784 static __inline struct mbuf *
m_gethdr(int how,short type)785 m_gethdr(int how, short type)
786 {
787 struct mbuf *m;
788 struct mb_args args;
789
790 args.flags = M_PKTHDR;
791 args.type = type;
792 m = uma_zalloc_arg(zone_mbuf, &args, how);
793 MBUF_PROBE3(m__gethdr, how, type, m);
794 return (m);
795 }
796
797 static __inline struct mbuf *
m_getcl(int how,short type,int flags)798 m_getcl(int how, short type, int flags)
799 {
800 struct mbuf *m;
801 struct mb_args args;
802
803 args.flags = flags;
804 args.type = type;
805 m = uma_zalloc_arg(zone_pack, &args, how);
806 MBUF_PROBE4(m__getcl, how, type, flags, m);
807 return (m);
808 }
809
810 /*
811 * XXX: m_cljset() is a dangerous API. One must attach only a new,
812 * unreferenced cluster to an mbuf(9). It is not possible to assert
813 * that, so care can be taken only by users of the API.
814 */
815 static __inline void
m_cljset(struct mbuf * m,void * cl,int type)816 m_cljset(struct mbuf *m, void *cl, int type)
817 {
818 int size;
819
820 switch (type) {
821 case EXT_CLUSTER:
822 size = MCLBYTES;
823 break;
824 #if MJUMPAGESIZE != MCLBYTES
825 case EXT_JUMBOP:
826 size = MJUMPAGESIZE;
827 break;
828 #endif
829 case EXT_JUMBO9:
830 size = MJUM9BYTES;
831 break;
832 case EXT_JUMBO16:
833 size = MJUM16BYTES;
834 break;
835 default:
836 panic("%s: unknown cluster type %d", __func__, type);
837 break;
838 }
839
840 m->m_data = m->m_ext.ext_buf = cl;
841 m->m_ext.ext_free = m->m_ext.ext_arg1 = m->m_ext.ext_arg2 = NULL;
842 m->m_ext.ext_size = size;
843 m->m_ext.ext_type = type;
844 m->m_ext.ext_flags = EXT_FLAG_EMBREF;
845 m->m_ext.ext_count = 1;
846 m->m_flags |= M_EXT;
847 MBUF_PROBE3(m__cljset, m, cl, type);
848 }
849
850 static __inline void
m_chtype(struct mbuf * m,short new_type)851 m_chtype(struct mbuf *m, short new_type)
852 {
853
854 m->m_type = new_type;
855 }
856
857 static __inline void
m_clrprotoflags(struct mbuf * m)858 m_clrprotoflags(struct mbuf *m)
859 {
860
861 while (m) {
862 m->m_flags &= ~M_PROTOFLAGS;
863 m = m->m_next;
864 }
865 }
866
867 static __inline struct mbuf *
m_last(struct mbuf * m)868 m_last(struct mbuf *m)
869 {
870
871 while (m->m_next)
872 m = m->m_next;
873 return (m);
874 }
875
876 static inline u_int
m_extrefcnt(struct mbuf * m)877 m_extrefcnt(struct mbuf *m)
878 {
879
880 KASSERT(m->m_flags & M_EXT, ("%s: M_EXT missing", __func__));
881
882 return ((m->m_ext.ext_flags & EXT_FLAG_EMBREF) ? m->m_ext.ext_count :
883 *m->m_ext.ext_cnt);
884 }
885
886 /*
887 * mbuf, cluster, and external object allocation macros (for compatibility
888 * purposes).
889 */
890 #define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from))
891 #define MGET(m, how, type) ((m) = m_get((how), (type)))
892 #define MGETHDR(m, how, type) ((m) = m_gethdr((how), (type)))
893 #define MCLGET(m, how) m_clget((m), (how))
894 #define MEXTADD(m, buf, size, free, arg1, arg2, flags, type) \
895 m_extadd((m), (char *)(buf), (size), (free), (arg1), (arg2), \
896 (flags), (type))
897 #define m_getm(m, len, how, type) \
898 m_getm2((m), (len), (how), (type), M_PKTHDR)
899
900 /*
901 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this can
902 * be both the local data payload, or an external buffer area, depending on
903 * whether M_EXT is set).
904 */
905 #define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && \
906 (!(((m)->m_flags & M_EXT)) || \
907 (m_extrefcnt(m) == 1)))
908
909 /* Check if the supplied mbuf has a packet header, or else panic. */
910 #define M_ASSERTPKTHDR(m) \
911 KASSERT((m) != NULL && (m)->m_flags & M_PKTHDR, \
912 ("%s: no mbuf packet header!", __func__))
913
914 /*
915 * Ensure that the supplied mbuf is a valid, non-free mbuf.
916 *
917 * XXX: Broken at the moment. Need some UMA magic to make it work again.
918 */
919 #define M_ASSERTVALID(m) \
920 KASSERT((((struct mbuf *)m)->m_flags & 0) == 0, \
921 ("%s: attempted use of a free mbuf!", __func__))
922
923 /*
924 * Return the address of the start of the buffer associated with an mbuf,
925 * handling external storage, packet-header mbufs, and regular data mbufs.
926 */
927 #define M_START(m) \
928 (((m)->m_flags & M_EXT) ? (m)->m_ext.ext_buf : \
929 ((m)->m_flags & M_PKTHDR) ? &(m)->m_pktdat[0] : \
930 &(m)->m_dat[0])
931
932 /*
933 * Return the size of the buffer associated with an mbuf, handling external
934 * storage, packet-header mbufs, and regular data mbufs.
935 */
936 #define M_SIZE(m) \
937 (((m)->m_flags & M_EXT) ? (m)->m_ext.ext_size : \
938 ((m)->m_flags & M_PKTHDR) ? MHLEN : \
939 MLEN)
940
941 /*
942 * Set the m_data pointer of a newly allocated mbuf to place an object of the
943 * specified size at the end of the mbuf, longword aligned.
944 *
945 * NB: Historically, we had M_ALIGN(), MH_ALIGN(), and MEXT_ALIGN() as
946 * separate macros, each asserting that it was called at the proper moment.
947 * This required callers to themselves test the storage type and call the
948 * right one. Rather than require callers to be aware of those layout
949 * decisions, we centralize here.
950 */
951 static __inline void
m_align(struct mbuf * m,int len)952 m_align(struct mbuf *m, int len)
953 {
954 #ifdef INVARIANTS
955 const char *msg = "%s: not a virgin mbuf";
956 #endif
957 int adjust;
958
959 KASSERT(m->m_data == M_START(m), (msg, __func__));
960
961 adjust = M_SIZE(m) - len;
962 m->m_data += adjust &~ (sizeof(long)-1);
963 }
964
965 #define M_ALIGN(m, len) m_align(m, len)
966 #define MH_ALIGN(m, len) m_align(m, len)
967 #define MEXT_ALIGN(m, len) m_align(m, len)
968
969 /*
970 * Compute the amount of space available before the current start of data in
971 * an mbuf.
972 *
973 * The M_WRITABLE() is a temporary, conservative safety measure: the burden
974 * of checking writability of the mbuf data area rests solely with the caller.
975 *
976 * NB: In previous versions, M_LEADINGSPACE() would only check M_WRITABLE()
977 * for mbufs with external storage. We now allow mbuf-embedded data to be
978 * read-only as well.
979 */
980 #define M_LEADINGSPACE(m) \
981 (M_WRITABLE(m) ? ((m)->m_data - M_START(m)) : 0)
982
983 /*
984 * Compute the amount of space available after the end of data in an mbuf.
985 *
986 * The M_WRITABLE() is a temporary, conservative safety measure: the burden
987 * of checking writability of the mbuf data area rests solely with the caller.
988 *
989 * NB: In previous versions, M_TRAILINGSPACE() would only check M_WRITABLE()
990 * for mbufs with external storage. We now allow mbuf-embedded data to be
991 * read-only as well.
992 */
993 #define M_TRAILINGSPACE(m) \
994 (M_WRITABLE(m) ? \
995 ((M_START(m) + M_SIZE(m)) - ((m)->m_data + (m)->m_len)) : 0)
996
997 /*
998 * Arrange to prepend space of size plen to mbuf m. If a new mbuf must be
999 * allocated, how specifies whether to wait. If the allocation fails, the
1000 * original mbuf chain is freed and m is set to NULL.
1001 */
1002 #define M_PREPEND(m, plen, how) do { \
1003 struct mbuf **_mmp = &(m); \
1004 struct mbuf *_mm = *_mmp; \
1005 int _mplen = (plen); \
1006 int __mhow = (how); \
1007 \
1008 MBUF_CHECKSLEEP(how); \
1009 if (M_LEADINGSPACE(_mm) >= _mplen) { \
1010 _mm->m_data -= _mplen; \
1011 _mm->m_len += _mplen; \
1012 } else \
1013 _mm = m_prepend(_mm, _mplen, __mhow); \
1014 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \
1015 _mm->m_pkthdr.len += _mplen; \
1016 *_mmp = _mm; \
1017 } while (0)
1018
1019 /*
1020 * Change mbuf to new type. This is a relatively expensive operation and
1021 * should be avoided.
1022 */
1023 #define MCHTYPE(m, t) m_chtype((m), (t))
1024
1025 /* Length to m_copy to copy all. */
1026 #define M_COPYALL 1000000000
1027
1028 extern int max_datalen; /* MHLEN - max_hdr */
1029 extern int max_hdr; /* Largest link + protocol header */
1030 extern int max_linkhdr; /* Largest link-level header */
1031 extern int max_protohdr; /* Largest protocol header */
1032 extern int nmbclusters; /* Maximum number of clusters */
1033
1034 /*-
1035 * Network packets may have annotations attached by affixing a list of
1036 * "packet tags" to the pkthdr structure. Packet tags are dynamically
1037 * allocated semi-opaque data structures that have a fixed header
1038 * (struct m_tag) that specifies the size of the memory block and a
1039 * <cookie,type> pair that identifies it. The cookie is a 32-bit unique
1040 * unsigned value used to identify a module or ABI. By convention this value
1041 * is chosen as the date+time that the module is created, expressed as the
1042 * number of seconds since the epoch (e.g., using date -u +'%s'). The type
1043 * value is an ABI/module-specific value that identifies a particular
1044 * annotation and is private to the module. For compatibility with systems
1045 * like OpenBSD that define packet tags w/o an ABI/module cookie, the value
1046 * PACKET_ABI_COMPAT is used to implement m_tag_get and m_tag_find
1047 * compatibility shim functions and several tag types are defined below.
1048 * Users that do not require compatibility should use a private cookie value
1049 * so that packet tag-related definitions can be maintained privately.
1050 *
1051 * Note that the packet tag returned by m_tag_alloc has the default memory
1052 * alignment implemented by malloc. To reference private data one can use a
1053 * construct like:
1054 *
1055 * struct m_tag *mtag = m_tag_alloc(...);
1056 * struct foo *p = (struct foo *)(mtag+1);
1057 *
1058 * if the alignment of struct m_tag is sufficient for referencing members of
1059 * struct foo. Otherwise it is necessary to embed struct m_tag within the
1060 * private data structure to insure proper alignment; e.g.,
1061 *
1062 * struct foo {
1063 * struct m_tag tag;
1064 * ...
1065 * };
1066 * struct foo *p = (struct foo *) m_tag_alloc(...);
1067 * struct m_tag *mtag = &p->tag;
1068 */
1069
1070 /*
1071 * Persistent tags stay with an mbuf until the mbuf is reclaimed. Otherwise
1072 * tags are expected to ``vanish'' when they pass through a network
1073 * interface. For most interfaces this happens normally as the tags are
1074 * reclaimed when the mbuf is free'd. However in some special cases
1075 * reclaiming must be done manually. An example is packets that pass through
1076 * the loopback interface. Also, one must be careful to do this when
1077 * ``turning around'' packets (e.g., icmp_reflect).
1078 *
1079 * To mark a tag persistent bit-or this flag in when defining the tag id.
1080 * The tag will then be treated as described above.
1081 */
1082 #define MTAG_PERSISTENT 0x800
1083
1084 #define PACKET_TAG_NONE 0 /* Nadda */
1085
1086 /* Packet tags for use with PACKET_ABI_COMPAT. */
1087 #define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */
1088 #define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */
1089 #define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */
1090 #define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */
1091 #define PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO 5 /* NIC notifies IPsec */
1092 #define PACKET_TAG_IPSEC_PENDING_TDB 6 /* Reminder to do IPsec */
1093 #define PACKET_TAG_BRIDGE 7 /* Bridge processing done */
1094 #define PACKET_TAG_GIF 8 /* GIF processing done */
1095 #define PACKET_TAG_GRE 9 /* GRE processing done */
1096 #define PACKET_TAG_IN_PACKET_CHECKSUM 10 /* NIC checksumming done */
1097 #define PACKET_TAG_ENCAP 11 /* Encap. processing */
1098 #define PACKET_TAG_IPSEC_SOCKET 12 /* IPSEC socket ref */
1099 #define PACKET_TAG_IPSEC_HISTORY 13 /* IPSEC history */
1100 #define PACKET_TAG_IPV6_INPUT 14 /* IPV6 input processing */
1101 #define PACKET_TAG_DUMMYNET 15 /* dummynet info */
1102 #define PACKET_TAG_DIVERT 17 /* divert info */
1103 #define PACKET_TAG_IPFORWARD 18 /* ipforward info */
1104 #define PACKET_TAG_MACLABEL (19 | MTAG_PERSISTENT) /* MAC label */
1105 #define PACKET_TAG_PF (21 | MTAG_PERSISTENT) /* PF/ALTQ information */
1106 #define PACKET_TAG_RTSOCKFAM 25 /* rtsock sa family */
1107 #define PACKET_TAG_IPOPTIONS 27 /* Saved IP options */
1108 #define PACKET_TAG_CARP 28 /* CARP info */
1109 #define PACKET_TAG_IPSEC_NAT_T_PORTS 29 /* two uint16_t */
1110 #define PACKET_TAG_ND_OUTGOING 30 /* ND outgoing */
1111
1112 /* Specific cookies and tags. */
1113
1114 /* Packet tag routines. */
1115 struct m_tag *m_tag_alloc(u_int32_t, int, int, int);
1116 void m_tag_delete(struct mbuf *, struct m_tag *);
1117 void m_tag_delete_chain(struct mbuf *, struct m_tag *);
1118 void m_tag_free_default(struct m_tag *);
1119 struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *);
1120 struct m_tag *m_tag_copy(struct m_tag *, int);
1121 int m_tag_copy_chain(struct mbuf *, const struct mbuf *, int);
1122 void m_tag_delete_nonpersistent(struct mbuf *);
1123
1124 /*
1125 * Initialize the list of tags associated with an mbuf.
1126 */
1127 static __inline void
m_tag_init(struct mbuf * m)1128 m_tag_init(struct mbuf *m)
1129 {
1130
1131 SLIST_INIT(&m->m_pkthdr.tags);
1132 }
1133
1134 /*
1135 * Set up the contents of a tag. Note that this does not fill in the free
1136 * method; the caller is expected to do that.
1137 *
1138 * XXX probably should be called m_tag_init, but that was already taken.
1139 */
1140 static __inline void
m_tag_setup(struct m_tag * t,u_int32_t cookie,int type,int len)1141 m_tag_setup(struct m_tag *t, u_int32_t cookie, int type, int len)
1142 {
1143
1144 t->m_tag_id = type;
1145 t->m_tag_len = len;
1146 t->m_tag_cookie = cookie;
1147 }
1148
1149 /*
1150 * Reclaim resources associated with a tag.
1151 */
1152 static __inline void
m_tag_free(struct m_tag * t)1153 m_tag_free(struct m_tag *t)
1154 {
1155
1156 (*t->m_tag_free)(t);
1157 }
1158
1159 /*
1160 * Return the first tag associated with an mbuf.
1161 */
1162 static __inline struct m_tag *
m_tag_first(struct mbuf * m)1163 m_tag_first(struct mbuf *m)
1164 {
1165
1166 return (SLIST_FIRST(&m->m_pkthdr.tags));
1167 }
1168
1169 /*
1170 * Return the next tag in the list of tags associated with an mbuf.
1171 */
1172 static __inline struct m_tag *
m_tag_next(struct mbuf * m __unused,struct m_tag * t)1173 m_tag_next(struct mbuf *m __unused, struct m_tag *t)
1174 {
1175
1176 return (SLIST_NEXT(t, m_tag_link));
1177 }
1178
1179 /*
1180 * Prepend a tag to the list of tags associated with an mbuf.
1181 */
1182 static __inline void
m_tag_prepend(struct mbuf * m,struct m_tag * t)1183 m_tag_prepend(struct mbuf *m, struct m_tag *t)
1184 {
1185
1186 SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link);
1187 }
1188
1189 /*
1190 * Unlink a tag from the list of tags associated with an mbuf.
1191 */
1192 static __inline void
m_tag_unlink(struct mbuf * m,struct m_tag * t)1193 m_tag_unlink(struct mbuf *m, struct m_tag *t)
1194 {
1195
1196 SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link);
1197 }
1198
1199 /* These are for OpenBSD compatibility. */
1200 #define MTAG_ABI_COMPAT 0 /* compatibility ABI */
1201
1202 static __inline struct m_tag *
m_tag_get(int type,int length,int wait)1203 m_tag_get(int type, int length, int wait)
1204 {
1205 return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait));
1206 }
1207
1208 static __inline struct m_tag *
m_tag_find(struct mbuf * m,int type,struct m_tag * start)1209 m_tag_find(struct mbuf *m, int type, struct m_tag *start)
1210 {
1211 return (SLIST_EMPTY(&m->m_pkthdr.tags) ? (struct m_tag *)NULL :
1212 m_tag_locate(m, MTAG_ABI_COMPAT, type, start));
1213 }
1214
1215 static __inline struct mbuf *
m_free(struct mbuf * m)1216 m_free(struct mbuf *m)
1217 {
1218 struct mbuf *n = m->m_next;
1219
1220 MBUF_PROBE1(m__free, m);
1221 if ((m->m_flags & (M_PKTHDR|M_NOFREE)) == (M_PKTHDR|M_NOFREE))
1222 m_tag_delete_chain(m, NULL);
1223 if (m->m_flags & M_EXT)
1224 mb_free_ext(m);
1225 else if ((m->m_flags & M_NOFREE) == 0)
1226 uma_zfree(zone_mbuf, m);
1227 return (n);
1228 }
1229
1230 static __inline int
rt_m_getfib(struct mbuf * m)1231 rt_m_getfib(struct mbuf *m)
1232 {
1233 KASSERT(m->m_flags & M_PKTHDR , ("Attempt to get FIB from non header mbuf."));
1234 return (m->m_pkthdr.fibnum);
1235 }
1236
1237 #define M_GETFIB(_m) rt_m_getfib(_m)
1238
1239 #define M_SETFIB(_m, _fib) do { \
1240 KASSERT((_m)->m_flags & M_PKTHDR, ("Attempt to set FIB on non header mbuf.")); \
1241 ((_m)->m_pkthdr.fibnum) = (_fib); \
1242 } while (0)
1243
1244 /* flags passed as first argument for "m_ether_tcpip_hash()" */
1245 #define MBUF_HASHFLAG_L2 (1 << 2)
1246 #define MBUF_HASHFLAG_L3 (1 << 3)
1247 #define MBUF_HASHFLAG_L4 (1 << 4)
1248
1249 /* mbuf hashing helper routines */
1250 uint32_t m_ether_tcpip_hash_init(void);
1251 uint32_t m_ether_tcpip_hash(const uint32_t, const struct mbuf *, const uint32_t);
1252
1253 #ifdef MBUF_PROFILING
1254 void m_profile(struct mbuf *m);
1255 #define M_PROFILE(m) m_profile(m)
1256 #else
1257 #define M_PROFILE(m)
1258 #endif
1259
1260 struct mbufq {
1261 STAILQ_HEAD(, mbuf) mq_head;
1262 int mq_len;
1263 int mq_maxlen;
1264 };
1265
1266 static inline void
mbufq_init(struct mbufq * mq,int maxlen)1267 mbufq_init(struct mbufq *mq, int maxlen)
1268 {
1269
1270 STAILQ_INIT(&mq->mq_head);
1271 mq->mq_maxlen = maxlen;
1272 mq->mq_len = 0;
1273 }
1274
1275 static inline struct mbuf *
mbufq_flush(struct mbufq * mq)1276 mbufq_flush(struct mbufq *mq)
1277 {
1278 struct mbuf *m;
1279
1280 m = STAILQ_FIRST(&mq->mq_head);
1281 STAILQ_INIT(&mq->mq_head);
1282 mq->mq_len = 0;
1283 return (m);
1284 }
1285
1286 static inline void
mbufq_drain(struct mbufq * mq)1287 mbufq_drain(struct mbufq *mq)
1288 {
1289 struct mbuf *m, *n;
1290
1291 n = mbufq_flush(mq);
1292 while ((m = n) != NULL) {
1293 n = STAILQ_NEXT(m, m_stailqpkt);
1294 m_freem(m);
1295 }
1296 }
1297
1298 static inline struct mbuf *
mbufq_first(const struct mbufq * mq)1299 mbufq_first(const struct mbufq *mq)
1300 {
1301
1302 return (STAILQ_FIRST(&mq->mq_head));
1303 }
1304
1305 static inline struct mbuf *
mbufq_last(const struct mbufq * mq)1306 mbufq_last(const struct mbufq *mq)
1307 {
1308
1309 return (STAILQ_LAST(&mq->mq_head, mbuf, m_stailqpkt));
1310 }
1311
1312 static inline int
mbufq_full(const struct mbufq * mq)1313 mbufq_full(const struct mbufq *mq)
1314 {
1315
1316 return (mq->mq_len >= mq->mq_maxlen);
1317 }
1318
1319 static inline int
mbufq_len(const struct mbufq * mq)1320 mbufq_len(const struct mbufq *mq)
1321 {
1322
1323 return (mq->mq_len);
1324 }
1325
1326 static inline int
mbufq_enqueue(struct mbufq * mq,struct mbuf * m)1327 mbufq_enqueue(struct mbufq *mq, struct mbuf *m)
1328 {
1329
1330 if (mbufq_full(mq))
1331 return (ENOBUFS);
1332 STAILQ_INSERT_TAIL(&mq->mq_head, m, m_stailqpkt);
1333 mq->mq_len++;
1334 return (0);
1335 }
1336
1337 static inline struct mbuf *
mbufq_dequeue(struct mbufq * mq)1338 mbufq_dequeue(struct mbufq *mq)
1339 {
1340 struct mbuf *m;
1341
1342 m = STAILQ_FIRST(&mq->mq_head);
1343 if (m) {
1344 STAILQ_REMOVE_HEAD(&mq->mq_head, m_stailqpkt);
1345 m->m_nextpkt = NULL;
1346 mq->mq_len--;
1347 }
1348 return (m);
1349 }
1350
1351 static inline void
mbufq_prepend(struct mbufq * mq,struct mbuf * m)1352 mbufq_prepend(struct mbufq *mq, struct mbuf *m)
1353 {
1354
1355 STAILQ_INSERT_HEAD(&mq->mq_head, m, m_stailqpkt);
1356 mq->mq_len++;
1357 }
1358
1359 /*
1360 * Note: this doesn't enforce the maximum list size for dst.
1361 */
1362 static inline void
mbufq_concat(struct mbufq * mq_dst,struct mbufq * mq_src)1363 mbufq_concat(struct mbufq *mq_dst, struct mbufq *mq_src)
1364 {
1365
1366 mq_dst->mq_len += mq_src->mq_len;
1367 STAILQ_CONCAT(&mq_dst->mq_head, &mq_src->mq_head);
1368 mq_src->mq_len = 0;
1369 }
1370
1371 #ifdef _SYS_TIMESPEC_H_
1372 static inline void
mbuf_tstmp2timespec(struct mbuf * m,struct timespec * ts)1373 mbuf_tstmp2timespec(struct mbuf *m, struct timespec *ts)
1374 {
1375
1376 KASSERT((m->m_flags & M_PKTHDR) != 0, ("mbuf %p no M_PKTHDR", m));
1377 KASSERT((m->m_flags & M_TSTMP) != 0, ("mbuf %p no M_TSTMP", m));
1378 ts->tv_sec = m->m_pkthdr.rcv_tstmp / 1000000000;
1379 ts->tv_nsec = m->m_pkthdr.rcv_tstmp % 1000000000;
1380 }
1381 #endif
1382
1383 #ifdef NETDUMP
1384 /* Invoked from the netdump client code. */
1385 void netdump_mbuf_drain(void);
1386 void netdump_mbuf_dump(void);
1387 void netdump_mbuf_reinit(int nmbuf, int nclust, int clsize);
1388 #endif
1389
1390 #endif /* _KERNEL */
1391 #endif /* !_SYS_MBUF_H_ */
1392