xref: /freebsd/sys/sys/mbuf.h (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
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 <sys/refcount.h>
44 #include <vm/uma.h>
45 
46 #include <sys/sdt.h>
47 
48 #define	MBUF_PROBE1(probe, arg0)					\
49 	SDT_PROBE1(sdt, , , probe, arg0)
50 #define	MBUF_PROBE2(probe, arg0, arg1)					\
51 	SDT_PROBE2(sdt, , , probe, arg0, arg1)
52 #define	MBUF_PROBE3(probe, arg0, arg1, arg2)				\
53 	SDT_PROBE3(sdt, , , probe, arg0, arg1, arg2)
54 #define	MBUF_PROBE4(probe, arg0, arg1, arg2, arg3)			\
55 	SDT_PROBE4(sdt, , , probe, arg0, arg1, arg2, arg3)
56 #define	MBUF_PROBE5(probe, arg0, arg1, arg2, arg3, arg4)		\
57 	SDT_PROBE5(sdt, , , probe, arg0, arg1, arg2, arg3, arg4)
58 
59 SDT_PROBE_DECLARE(sdt, , , m__init);
60 SDT_PROBE_DECLARE(sdt, , , m__gethdr_raw);
61 SDT_PROBE_DECLARE(sdt, , , m__gethdr);
62 SDT_PROBE_DECLARE(sdt, , , m__get_raw);
63 SDT_PROBE_DECLARE(sdt, , , m__get);
64 SDT_PROBE_DECLARE(sdt, , , m__getcl);
65 SDT_PROBE_DECLARE(sdt, , , m__getjcl);
66 SDT_PROBE_DECLARE(sdt, , , m__clget);
67 SDT_PROBE_DECLARE(sdt, , , m__cljget);
68 SDT_PROBE_DECLARE(sdt, , , m__cljset);
69 SDT_PROBE_DECLARE(sdt, , , m__free);
70 SDT_PROBE_DECLARE(sdt, , , m__freem);
71 
72 #endif /* _KERNEL */
73 
74 /*
75  * Mbufs are of a single size, MSIZE (sys/param.h), which includes overhead.
76  * An mbuf may add a single "mbuf cluster" of size MCLBYTES (also in
77  * sys/param.h), which has no additional overhead and is used instead of the
78  * internal data area; this is done when at least MINCLSIZE of data must be
79  * stored.  Additionally, it is possible to allocate a separate buffer
80  * externally and attach it to the mbuf in a way similar to that of mbuf
81  * clusters.
82  *
83  * NB: These calculation do not take actual compiler-induced alignment and
84  * padding inside the complete struct mbuf into account.  Appropriate
85  * attention is required when changing members of struct mbuf.
86  *
87  * MLEN is data length in a normal mbuf.
88  * MHLEN is data length in an mbuf with pktheader.
89  * MINCLSIZE is a smallest amount of data that should be put into cluster.
90  *
91  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
92  * they are sensible.
93  */
94 struct mbuf;
95 #define	MHSIZE		offsetof(struct mbuf, m_dat)
96 #define	MPKTHSIZE	offsetof(struct mbuf, m_pktdat)
97 #define	MLEN		((int)(MSIZE - MHSIZE))
98 #define	MHLEN		((int)(MSIZE - MPKTHSIZE))
99 #define	MINCLSIZE	(MHLEN + 1)
100 #define	M_NODOM		255
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 if_snd_tag_sw;
139 
140 struct m_snd_tag {
141 	struct ifnet *ifp;		/* network interface tag belongs to */
142 	const struct if_snd_tag_sw *sw;
143 	volatile u_int refcount;
144 };
145 
146 /*
147  * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set.
148  * Size ILP32: 56
149  *	 LP64: 64
150  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
151  * they are correct.
152  */
153 struct pkthdr {
154 	union {
155 		struct m_snd_tag *snd_tag;	/* send tag, if any */
156 		struct ifnet	*rcvif;		/* rcv interface */
157 		struct {
158 			uint16_t rcvidx;	/* rcv interface index ... */
159 			uint16_t rcvgen;	/* ... and generation count */
160 		};
161 	};
162 	union {
163 		struct ifnet	*leaf_rcvif;	/* leaf rcv interface */
164 		struct {
165 			uint16_t leaf_rcvidx;	/* leaf rcv interface index ... */
166 			uint16_t leaf_rcvgen;	/* ... and generation count */
167 		};
168 	};
169 	SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */
170 	int32_t		 len;		/* total packet length */
171 
172 	/* Layer crossing persistent information. */
173 	uint32_t	 flowid;	/* packet's 4-tuple system */
174 	uint32_t	 csum_flags;	/* checksum and offload features */
175 	uint16_t	 fibnum;	/* this packet should use this fib */
176 	uint8_t		 numa_domain;	/* NUMA domain of recvd pkt */
177 	uint8_t		 rsstype;	/* hash type */
178 #if !defined(__LP64__)
179 	uint32_t	 pad;		/* pad for 64bit alignment */
180 #endif
181 	union {
182 		uint64_t	rcv_tstmp;	/* timestamp in ns */
183 		struct {
184 			uint8_t		 l2hlen;	/* layer 2 hdr len */
185 			uint8_t		 l3hlen;	/* layer 3 hdr len */
186 			uint8_t		 l4hlen;	/* layer 4 hdr len */
187 			uint8_t		 l5hlen;	/* layer 5 hdr len */
188 			uint8_t		 inner_l2hlen;
189 			uint8_t		 inner_l3hlen;
190 			uint8_t		 inner_l4hlen;
191 			uint8_t		 inner_l5hlen;
192 		};
193 	};
194 	union {
195 		uint8_t  eight[8];
196 		uint16_t sixteen[4];
197 		uint32_t thirtytwo[2];
198 		uint64_t sixtyfour[1];
199 		uintptr_t unintptr[1];
200 		void	*ptr;
201 	} PH_per;
202 
203 	/* Layer specific non-persistent local storage for reassembly, etc. */
204 	union {
205 		union {
206 			uint8_t  eight[8];
207 			uint16_t sixteen[4];
208 			uint32_t thirtytwo[2];
209 			uint64_t sixtyfour[1];
210 			uintptr_t unintptr[1];
211 			void 	*ptr;
212 		} PH_loc;
213 		/* Upon allocation: total packet memory consumption. */
214 		u_int	memlen;
215 	};
216 };
217 #define	ether_vtag	PH_per.sixteen[0]
218 #define tcp_tun_port	PH_per.sixteen[0] /* outbound */
219 #define	vt_nrecs	PH_per.sixteen[0]	  /* mld and v6-ND */
220 #define	tso_segsz	PH_per.sixteen[1] /* inbound after LRO */
221 #define	lro_nsegs	tso_segsz	  /* inbound after LRO */
222 #define	csum_data	PH_per.thirtytwo[1] /* inbound from hardware up */
223 #define	lro_tcp_d_len	PH_loc.sixteen[0] /* inbound during LRO (no reassembly) */
224 #define	lro_tcp_d_csum	PH_loc.sixteen[1] /* inbound during LRO (no reassembly) */
225 #define	lro_tcp_h_off	PH_loc.sixteen[2] /* inbound during LRO (no reassembly) */
226 #define	lro_etype	PH_loc.sixteen[3] /* inbound during LRO (no reassembly) */
227 /* Note PH_loc is used during IP reassembly (all 8 bytes as a ptr) */
228 
229 /*
230  * TLS records for TLS 1.0-1.2 can have the following header lengths:
231  * - 5 (AES-CBC with implicit IV)
232  * - 21 (AES-CBC with explicit IV)
233  * - 13 (AES-GCM with 8 byte explicit IV)
234  */
235 #define	MBUF_PEXT_HDR_LEN	23
236 
237 /*
238  * TLS records for TLS 1.0-1.2 can have the following maximum trailer
239  * lengths:
240  * - 16 (AES-GCM)
241  * - 36 (AES-CBC with SHA1 and up to 16 bytes of padding)
242  * - 48 (AES-CBC with SHA2-256 and up to 16 bytes of padding)
243  * - 64 (AES-CBC with SHA2-384 and up to 16 bytes of padding)
244  */
245 #define	MBUF_PEXT_TRAIL_LEN	64
246 
247 #if defined(__LP64__)
248 #define MBUF_PEXT_MAX_PGS (40 / sizeof(vm_paddr_t))
249 #else
250 #define MBUF_PEXT_MAX_PGS (64 / sizeof(vm_paddr_t))
251 #endif
252 
253 #define	MBUF_PEXT_MAX_BYTES						\
254     (MBUF_PEXT_MAX_PGS * PAGE_SIZE + MBUF_PEXT_HDR_LEN + MBUF_PEXT_TRAIL_LEN)
255 
256 struct ktls_session;
257 struct socket;
258 
259 /*
260  * Description of external storage mapped into mbuf; valid only if M_EXT is
261  * set.
262  * Size ILP32: 28
263  *	 LP64: 48
264  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
265  * they are correct.
266  */
267 typedef	void m_ext_free_t(struct mbuf *);
268 struct m_ext {
269 	union {
270 		/*
271 		 * If EXT_FLAG_EMBREF is set, then we use refcount in the
272 		 * mbuf, the 'ext_count' member.  Otherwise, we have a
273 		 * shadow copy and we use pointer 'ext_cnt'.  The original
274 		 * mbuf is responsible to carry the pointer to free routine
275 		 * and its arguments.  They aren't copied into shadows in
276 		 * mb_dupcl() to avoid dereferencing next cachelines.
277 		 */
278 		volatile u_int	 ext_count;
279 		volatile u_int	*ext_cnt;
280 	};
281 	uint32_t	 ext_size;	/* size of buffer, for ext_free */
282 	uint32_t	 ext_type:8,	/* type of external storage */
283 			 ext_flags:24;	/* external storage mbuf flags */
284 	union {
285 		struct {
286 			/*
287 			 * Regular M_EXT mbuf:
288 			 * o ext_buf always points to the external buffer.
289 			 * o ext_free (below) and two optional arguments
290 			 *   ext_arg1 and ext_arg2 store the free context for
291 			 *   the external storage.  They are set only in the
292 			 *   refcount carrying mbuf, the one with
293 			 *   EXT_FLAG_EMBREF flag, with exclusion for
294 			 *   EXT_EXTREF type, where the free context is copied
295 			 *   into all mbufs that use same external storage.
296 			 */
297 			char 	*ext_buf;	/* start of buffer */
298 #define	m_ext_copylen	offsetof(struct m_ext, ext_arg2)
299 			void	*ext_arg2;
300 		};
301 		struct {
302 			/*
303 			 * Multi-page M_EXTPG mbuf:
304 			 * o extpg_pa - page vector.
305 			 * o extpg_trail and extpg_hdr - TLS trailer and
306 			 *   header.
307 			 * Uses ext_free and may also use ext_arg1.
308 			 */
309 			vm_paddr_t	extpg_pa[MBUF_PEXT_MAX_PGS];
310 			char		extpg_trail[MBUF_PEXT_TRAIL_LEN];
311 			char		extpg_hdr[MBUF_PEXT_HDR_LEN];
312 			/* Pretend these 3 fields are part of mbuf itself. */
313 #define	m_epg_pa	m_ext.extpg_pa
314 #define	m_epg_trail	m_ext.extpg_trail
315 #define	m_epg_hdr	m_ext.extpg_hdr
316 #define	m_epg_ext_copylen	offsetof(struct m_ext, ext_free)
317 		};
318 	};
319 	/*
320 	 * Free method and optional argument pointer, both
321 	 * used by M_EXT and M_EXTPG.
322 	 */
323 	m_ext_free_t	*ext_free;
324 	void		*ext_arg1;
325 };
326 
327 /*
328  * The core of the mbuf object along with some shortcut defines for practical
329  * purposes.
330  */
331 struct mbuf {
332 	/*
333 	 * Header present at the beginning of every mbuf.
334 	 * Size ILP32: 24
335 	 *      LP64: 32
336 	 * Compile-time assertions in uipc_mbuf.c test these values to ensure
337 	 * that they are correct.
338 	 */
339 	union {	/* next buffer in chain */
340 		struct mbuf		*m_next;
341 		SLIST_ENTRY(mbuf)	m_slist;
342 		STAILQ_ENTRY(mbuf)	m_stailq;
343 	};
344 	union {	/* next chain in queue/record */
345 		struct mbuf		*m_nextpkt;
346 		SLIST_ENTRY(mbuf)	m_slistpkt;
347 		STAILQ_ENTRY(mbuf)	m_stailqpkt;
348 	};
349 	caddr_t		 m_data;	/* location of data */
350 	int32_t		 m_len;		/* amount of data in this mbuf */
351 	uint32_t	 m_type:8,	/* type of data in this mbuf */
352 			 m_flags:24;	/* flags; see below */
353 #if !defined(__LP64__)
354 	uint32_t	 m_pad;		/* pad for 64bit alignment */
355 #endif
356 
357 	/*
358 	 * A set of optional headers (packet header, external storage header)
359 	 * and internal data storage.  Historically, these arrays were sized
360 	 * to MHLEN (space left after a packet header) and MLEN (space left
361 	 * after only a regular mbuf header); they are now variable size in
362 	 * order to support future work on variable-size mbufs.
363 	 */
364 	union {
365 		struct {
366 			union {
367 				/* M_PKTHDR set. */
368 				struct pkthdr	m_pkthdr;
369 
370 				/* M_EXTPG set.
371 				 * Multi-page M_EXTPG mbuf has its meta data
372 				 * split between the below anonymous structure
373 				 * and m_ext.  It carries vector of pages,
374 				 * optional header and trailer char vectors
375 				 * and pointers to socket/TLS data.
376 				 */
377 #define	m_epg_startcopy		m_epg_npgs
378 #define	m_epg_endcopy		m_epg_stailq
379 				struct {
380 					/* Overall count of pages and count of
381 					 * pages with I/O pending. */
382 					uint8_t	m_epg_npgs;
383 					uint8_t	m_epg_nrdy;
384 					/* TLS header and trailer lengths.
385 					 * The data itself resides in m_ext. */
386 					uint8_t	m_epg_hdrlen;
387 					uint8_t	m_epg_trllen;
388 					/* Offset into 1st page and length of
389 					 * data in the last page. */
390 					uint16_t m_epg_1st_off;
391 					uint16_t m_epg_last_len;
392 					uint8_t	m_epg_flags;
393 #define	EPG_FLAG_ANON	0x1	/* Data can be encrypted in place. */
394 #define	EPG_FLAG_2FREE	0x2	/* Scheduled for free. */
395 					uint8_t	m_epg_record_type;
396 					uint8_t	__spare[2];
397 					int	m_epg_enc_cnt;
398 					struct ktls_session *m_epg_tls;
399 					struct socket	*m_epg_so;
400 					uint64_t	m_epg_seqno;
401 					STAILQ_ENTRY(mbuf) m_epg_stailq;
402 				};
403 			};
404 			union {
405 				/* M_EXT or M_EXTPG set. */
406 				struct m_ext	m_ext;
407 				/* M_PKTHDR set, neither M_EXT nor M_EXTPG. */
408 				char		m_pktdat[0];
409 			};
410 		};
411 		char	m_dat[0];			/* !M_PKTHDR, !M_EXT */
412 	};
413 };
414 
415 #ifdef _KERNEL
416 static inline int
417 m_epg_pagelen(const struct mbuf *m, int pidx, int pgoff)
418 {
419 
420 	KASSERT(pgoff == 0 || pidx == 0,
421 	    ("page %d with non-zero offset %d in %p", pidx, pgoff, m));
422 
423 	if (pidx == m->m_epg_npgs - 1) {
424 		return (m->m_epg_last_len);
425 	} else {
426 		return (PAGE_SIZE - pgoff);
427 	}
428 }
429 
430 #ifdef INVARIANTS
431 #define	MCHECK(ex, msg)	KASSERT((ex),				\
432 	    ("Multi page mbuf %p with " #msg " at %s:%d",	\
433 	    m, __FILE__, __LINE__))
434 /*
435  * NB: This expects a non-empty buffer (npgs > 0 and
436  * last_pg_len > 0).
437  */
438 #define	MBUF_EXT_PGS_ASSERT_SANITY(m)	do {				\
439 	MCHECK(m->m_epg_npgs > 0, "no valid pages");		\
440 	MCHECK(m->m_epg_npgs <= nitems(m->m_epg_pa),		\
441 	    "too many pages");						\
442 	MCHECK(m->m_epg_nrdy <= m->m_epg_npgs,			\
443 	    "too many ready pages");					\
444 	MCHECK(m->m_epg_1st_off < PAGE_SIZE,			\
445 		"too large page offset");				\
446 	MCHECK(m->m_epg_last_len > 0, "zero last page length");	\
447 	MCHECK(m->m_epg_last_len <= PAGE_SIZE,			\
448 	    "too large last page length");				\
449 	if (m->m_epg_npgs == 1)					\
450 		MCHECK(m->m_epg_1st_off +			\
451 		    m->m_epg_last_len <=	 PAGE_SIZE,		\
452 		    "single page too large");				\
453 	MCHECK(m->m_epg_hdrlen <= sizeof(m->m_epg_hdr),		\
454 	    "too large header length");					\
455 	MCHECK(m->m_epg_trllen <= sizeof(m->m_epg_trail),	\
456 	    "too large header length");					\
457 } while (0)
458 #else
459 #define	MBUF_EXT_PGS_ASSERT_SANITY(m)	do {} while (0)
460 #endif
461 #endif
462 
463 /*
464  * mbuf flags of global significance and layer crossing.
465  * Those of only protocol/layer specific significance are to be mapped
466  * to M_PROTO[1-11] and cleared at layer handoff boundaries.
467  * NB: Limited to the lower 24 bits.
468  */
469 #define	M_EXT		0x00000001 /* has associated external storage */
470 #define	M_PKTHDR	0x00000002 /* start of record */
471 #define	M_EOR		0x00000004 /* end of record */
472 #define	M_RDONLY	0x00000008 /* associated data is marked read-only */
473 #define	M_BCAST		0x00000010 /* send/received as link-level broadcast */
474 #define	M_MCAST		0x00000020 /* send/received as link-level multicast */
475 #define	M_PROMISC	0x00000040 /* packet was not for us */
476 #define	M_VLANTAG	0x00000080 /* ether_vtag is valid */
477 #define	M_EXTPG		0x00000100 /* has array of unmapped pages and TLS */
478 #define	M_NOFREE	0x00000200 /* do not free mbuf, embedded in cluster */
479 #define	M_TSTMP		0x00000400 /* rcv_tstmp field is valid */
480 #define	M_TSTMP_HPREC	0x00000800 /* rcv_tstmp is high-prec, typically
481 				      hw-stamped on port (useful for IEEE 1588
482 				      and 802.1AS) */
483 #define M_TSTMP_LRO	0x00001000 /* Time LRO pushed in pkt is valid in (PH_loc) */
484 
485 #define	M_PROTO1	0x00002000 /* protocol-specific */
486 #define	M_PROTO2	0x00004000 /* protocol-specific */
487 #define	M_PROTO3	0x00008000 /* protocol-specific */
488 #define	M_PROTO4	0x00010000 /* protocol-specific */
489 #define	M_PROTO5	0x00020000 /* protocol-specific */
490 #define	M_PROTO6	0x00040000 /* protocol-specific */
491 #define	M_PROTO7	0x00080000 /* protocol-specific */
492 #define	M_PROTO8	0x00100000 /* protocol-specific */
493 #define	M_PROTO9	0x00200000 /* protocol-specific */
494 #define	M_PROTO10	0x00400000 /* protocol-specific */
495 #define	M_PROTO11	0x00800000 /* protocol-specific */
496 
497 /*
498  * Flags to purge when crossing layers.
499  */
500 #define	M_PROTOFLAGS \
501     (M_PROTO1|M_PROTO2|M_PROTO3|M_PROTO4|M_PROTO5|M_PROTO6|M_PROTO7|M_PROTO8|\
502      M_PROTO9|M_PROTO10|M_PROTO11)
503 
504 /*
505  * Flags preserved when copying m_pkthdr.
506  */
507 #define M_COPYFLAGS \
508     (M_PKTHDR|M_EOR|M_RDONLY|M_BCAST|M_MCAST|M_PROMISC|M_VLANTAG|M_TSTMP| \
509      M_TSTMP_HPREC|M_TSTMP_LRO|M_PROTOFLAGS)
510 
511 /*
512  * Flags preserved during demote.
513  */
514 #define	M_DEMOTEFLAGS \
515     (M_EXT | M_RDONLY | M_NOFREE | M_EXTPG)
516 
517 /*
518  * Mbuf flag description for use with printf(9) %b identifier.
519  */
520 #define	M_FLAG_BITS \
521     "\20\1M_EXT\2M_PKTHDR\3M_EOR\4M_RDONLY\5M_BCAST\6M_MCAST" \
522     "\7M_PROMISC\10M_VLANTAG\11M_EXTPG\12M_NOFREE\13M_TSTMP\14M_TSTMP_HPREC\15M_TSTMP_LRO"
523 #define	M_FLAG_PROTOBITS \
524     "\16M_PROTO1\17M_PROTO2\20M_PROTO3\21M_PROTO4" \
525     "\22M_PROTO5\23M_PROTO6\24M_PROTO7\25M_PROTO8\26M_PROTO9" \
526     "\27M_PROTO10\28M_PROTO11"
527 #define	M_FLAG_PRINTF (M_FLAG_BITS M_FLAG_PROTOBITS)
528 
529 /*
530  * Network interface cards are able to hash protocol fields (such as IPv4
531  * addresses and TCP port numbers) classify packets into flows.  These flows
532  * can then be used to maintain ordering while delivering packets to the OS
533  * via parallel input queues, as well as to provide a stateless affinity
534  * model.  NIC drivers can pass up the hash via m->m_pkthdr.flowid, and set
535  * m_flag fields to indicate how the hash should be interpreted by the
536  * network stack.
537  *
538  * Most NICs support RSS, which provides ordering and explicit affinity, and
539  * use the hash m_flag bits to indicate what header fields were covered by
540  * the hash.  M_HASHTYPE_OPAQUE and M_HASHTYPE_OPAQUE_HASH can be set by non-
541  * RSS cards or configurations that provide an opaque flow identifier, allowing
542  * for ordering and distribution without explicit affinity.  Additionally,
543  * M_HASHTYPE_OPAQUE_HASH indicates that the flow identifier has hash
544  * properties.
545  *
546  * The meaning of the IPV6_EX suffix:
547  * "o  Home address from the home address option in the IPv6 destination
548  *     options header.  If the extension header is not present, use the Source
549  *     IPv6 Address.
550  *  o  IPv6 address that is contained in the Routing-Header-Type-2 from the
551  *     associated extension header.  If the extension header is not present,
552  *     use the Destination IPv6 Address."
553  * Quoted from:
554  * https://docs.microsoft.com/en-us/windows-hardware/drivers/network/rss-hashing-types#ndishashipv6ex
555  */
556 #define	M_HASHTYPE_HASHPROP		0x80	/* has hash properties */
557 #define	M_HASHTYPE_INNER		0x40	/* calculated from inner headers */
558 #define	M_HASHTYPE_HASH(t)		(M_HASHTYPE_HASHPROP | (t))
559 /* Microsoft RSS standard hash types */
560 #define	M_HASHTYPE_NONE			0
561 #define	M_HASHTYPE_RSS_IPV4		M_HASHTYPE_HASH(1) /* IPv4 2-tuple */
562 #define	M_HASHTYPE_RSS_TCP_IPV4		M_HASHTYPE_HASH(2) /* TCPv4 4-tuple */
563 #define	M_HASHTYPE_RSS_IPV6		M_HASHTYPE_HASH(3) /* IPv6 2-tuple */
564 #define	M_HASHTYPE_RSS_TCP_IPV6		M_HASHTYPE_HASH(4) /* TCPv6 4-tuple */
565 #define	M_HASHTYPE_RSS_IPV6_EX		M_HASHTYPE_HASH(5) /* IPv6 2-tuple +
566 							    * ext hdrs */
567 #define	M_HASHTYPE_RSS_TCP_IPV6_EX	M_HASHTYPE_HASH(6) /* TCPv6 4-tuple +
568 							    * ext hdrs */
569 #define	M_HASHTYPE_RSS_UDP_IPV4		M_HASHTYPE_HASH(7) /* IPv4 UDP 4-tuple*/
570 #define	M_HASHTYPE_RSS_UDP_IPV6		M_HASHTYPE_HASH(9) /* IPv6 UDP 4-tuple*/
571 #define	M_HASHTYPE_RSS_UDP_IPV6_EX	M_HASHTYPE_HASH(10)/* IPv6 UDP 4-tuple +
572 							    * ext hdrs */
573 
574 #define	M_HASHTYPE_OPAQUE		0x3f	/* ordering, not affinity */
575 #define	M_HASHTYPE_OPAQUE_HASH		M_HASHTYPE_HASH(M_HASHTYPE_OPAQUE)
576 						/* ordering+hash, not affinity*/
577 
578 #define	M_HASHTYPE_CLEAR(m)	((m)->m_pkthdr.rsstype = 0)
579 #define	M_HASHTYPE_GET(m)	((m)->m_pkthdr.rsstype & ~M_HASHTYPE_INNER)
580 #define	M_HASHTYPE_SET(m, v)	((m)->m_pkthdr.rsstype = (v))
581 #define	M_HASHTYPE_TEST(m, v)	(M_HASHTYPE_GET(m) == (v))
582 #define	M_HASHTYPE_ISHASH(m)	\
583     (((m)->m_pkthdr.rsstype & M_HASHTYPE_HASHPROP) != 0)
584 #define	M_HASHTYPE_SETINNER(m)	do {			\
585 	(m)->m_pkthdr.rsstype |= M_HASHTYPE_INNER;	\
586     } while (0)
587 
588 /*
589  * External mbuf storage buffer types.
590  */
591 #define	EXT_CLUSTER	1	/* mbuf cluster */
592 #define	EXT_SFBUF	2	/* sendfile(2)'s sf_buf */
593 #define	EXT_JUMBOP	3	/* jumbo cluster page sized */
594 #define	EXT_JUMBO9	4	/* jumbo cluster 9216 bytes */
595 #define	EXT_JUMBO16	5	/* jumbo cluster 16184 bytes */
596 #define	EXT_PACKET	6	/* mbuf+cluster from packet zone */
597 #define	EXT_MBUF	7	/* external mbuf reference */
598 #define	EXT_RXRING	8	/* data in NIC receive ring */
599 
600 #define	EXT_VENDOR1	224	/* for vendor-internal use */
601 #define	EXT_VENDOR2	225	/* for vendor-internal use */
602 #define	EXT_VENDOR3	226	/* for vendor-internal use */
603 #define	EXT_VENDOR4	227	/* for vendor-internal use */
604 
605 #define	EXT_EXP1	244	/* for experimental use */
606 #define	EXT_EXP2	245	/* for experimental use */
607 #define	EXT_EXP3	246	/* for experimental use */
608 #define	EXT_EXP4	247	/* for experimental use */
609 
610 #define	EXT_NET_DRV	252	/* custom ext_buf provided by net driver(s) */
611 #define	EXT_MOD_TYPE	253	/* custom module's ext_buf type */
612 #define	EXT_DISPOSABLE	254	/* can throw this buffer away w/page flipping */
613 #define	EXT_EXTREF	255	/* has externally maintained ext_cnt ptr */
614 
615 /*
616  * Flags for external mbuf buffer types.
617  * NB: limited to the lower 24 bits.
618  */
619 #define	EXT_FLAG_EMBREF		0x000001	/* embedded ext_count */
620 #define	EXT_FLAG_EXTREF		0x000002	/* external ext_cnt, notyet */
621 
622 #define	EXT_FLAG_NOFREE		0x000010	/* don't free mbuf to pool, notyet */
623 
624 #define	EXT_FLAG_VENDOR1	0x010000	/* These flags are vendor */
625 #define	EXT_FLAG_VENDOR2	0x020000	/* or submodule specific, */
626 #define	EXT_FLAG_VENDOR3	0x040000	/* not used by mbuf code. */
627 #define	EXT_FLAG_VENDOR4	0x080000	/* Set/read by submodule. */
628 
629 #define	EXT_FLAG_EXP1		0x100000	/* for experimental use */
630 #define	EXT_FLAG_EXP2		0x200000	/* for experimental use */
631 #define	EXT_FLAG_EXP3		0x400000	/* for experimental use */
632 #define	EXT_FLAG_EXP4		0x800000	/* for experimental use */
633 
634 /*
635  * EXT flag description for use with printf(9) %b identifier.
636  */
637 #define	EXT_FLAG_BITS \
638     "\20\1EXT_FLAG_EMBREF\2EXT_FLAG_EXTREF\5EXT_FLAG_NOFREE" \
639     "\21EXT_FLAG_VENDOR1\22EXT_FLAG_VENDOR2\23EXT_FLAG_VENDOR3" \
640     "\24EXT_FLAG_VENDOR4\25EXT_FLAG_EXP1\26EXT_FLAG_EXP2\27EXT_FLAG_EXP3" \
641     "\30EXT_FLAG_EXP4"
642 
643 /*
644  * Flags indicating checksum, segmentation and other offload work to be
645  * done, or already done, by hardware or lower layers.  It is split into
646  * separate inbound and outbound flags.
647  *
648  * Outbound flags that are set by upper protocol layers requesting lower
649  * layers, or ideally the hardware, to perform these offloading tasks.
650  * For outbound packets this field and its flags can be directly tested
651  * against ifnet if_hwassist.  Note that the outbound and the inbound flags do
652  * not collide right now but they could be allowed to (as long as the flags are
653  * scrubbed appropriately when the direction of an mbuf changes).  CSUM_BITS
654  * would also have to split into CSUM_BITS_TX and CSUM_BITS_RX.
655  *
656  * CSUM_INNER_<x> is the same as CSUM_<x> but it applies to the inner frame.
657  * The CSUM_ENCAP_<x> bits identify the outer encapsulation.
658  */
659 #define	CSUM_IP			0x00000001	/* IP header checksum offload */
660 #define	CSUM_IP_UDP		0x00000002	/* UDP checksum offload */
661 #define	CSUM_IP_TCP		0x00000004	/* TCP checksum offload */
662 #define	CSUM_IP_SCTP		0x00000008	/* SCTP checksum offload */
663 #define	CSUM_IP_TSO		0x00000010	/* TCP segmentation offload */
664 #define	CSUM_IP_ISCSI		0x00000020	/* iSCSI checksum offload */
665 
666 #define	CSUM_INNER_IP6_UDP	0x00000040
667 #define	CSUM_INNER_IP6_TCP	0x00000080
668 #define	CSUM_INNER_IP6_TSO	0x00000100
669 #define	CSUM_IP6_UDP		0x00000200	/* UDP checksum offload */
670 #define	CSUM_IP6_TCP		0x00000400	/* TCP checksum offload */
671 #define	CSUM_IP6_SCTP		0x00000800	/* SCTP checksum offload */
672 #define	CSUM_IP6_TSO		0x00001000	/* TCP segmentation offload */
673 #define	CSUM_IP6_ISCSI		0x00002000	/* iSCSI checksum offload */
674 
675 #define	CSUM_INNER_IP		0x00004000
676 #define	CSUM_INNER_IP_UDP	0x00008000
677 #define	CSUM_INNER_IP_TCP	0x00010000
678 #define	CSUM_INNER_IP_TSO	0x00020000
679 
680 #define	CSUM_ENCAP_VXLAN	0x00040000	/* VXLAN outer encapsulation */
681 #define	CSUM_ENCAP_RSVD1	0x00080000
682 
683 /* Inbound checksum support where the checksum was verified by hardware. */
684 #define	CSUM_INNER_L3_CALC	0x00100000
685 #define	CSUM_INNER_L3_VALID	0x00200000
686 #define	CSUM_INNER_L4_CALC	0x00400000
687 #define	CSUM_INNER_L4_VALID	0x00800000
688 #define	CSUM_L3_CALC		0x01000000	/* calculated layer 3 csum */
689 #define	CSUM_L3_VALID		0x02000000	/* checksum is correct */
690 #define	CSUM_L4_CALC		0x04000000	/* calculated layer 4 csum */
691 #define	CSUM_L4_VALID		0x08000000	/* checksum is correct */
692 #define	CSUM_L5_CALC		0x10000000	/* calculated layer 5 csum */
693 #define	CSUM_L5_VALID		0x20000000	/* checksum is correct */
694 #define	CSUM_COALESCED		0x40000000	/* contains merged segments */
695 
696 #define	CSUM_SND_TAG		0x80000000	/* Packet header has send tag */
697 
698 #define CSUM_FLAGS_TX (CSUM_IP | CSUM_IP_UDP | CSUM_IP_TCP | CSUM_IP_SCTP | \
699     CSUM_IP_TSO | CSUM_IP_ISCSI | CSUM_INNER_IP6_UDP | CSUM_INNER_IP6_TCP | \
700     CSUM_INNER_IP6_TSO | CSUM_IP6_UDP | CSUM_IP6_TCP | CSUM_IP6_SCTP | \
701     CSUM_IP6_TSO | CSUM_IP6_ISCSI | CSUM_INNER_IP | CSUM_INNER_IP_UDP | \
702     CSUM_INNER_IP_TCP | CSUM_INNER_IP_TSO | CSUM_ENCAP_VXLAN | \
703     CSUM_ENCAP_RSVD1 | CSUM_SND_TAG)
704 
705 #define CSUM_FLAGS_RX (CSUM_INNER_L3_CALC | CSUM_INNER_L3_VALID | \
706     CSUM_INNER_L4_CALC | CSUM_INNER_L4_VALID | CSUM_L3_CALC | CSUM_L3_VALID | \
707     CSUM_L4_CALC | CSUM_L4_VALID | CSUM_L5_CALC | CSUM_L5_VALID | \
708     CSUM_COALESCED)
709 
710 /*
711  * CSUM flag description for use with printf(9) %b identifier.
712  */
713 #define	CSUM_BITS \
714     "\20\1CSUM_IP\2CSUM_IP_UDP\3CSUM_IP_TCP\4CSUM_IP_SCTP\5CSUM_IP_TSO" \
715     "\6CSUM_IP_ISCSI\7CSUM_INNER_IP6_UDP\10CSUM_INNER_IP6_TCP" \
716     "\11CSUM_INNER_IP6_TSO\12CSUM_IP6_UDP\13CSUM_IP6_TCP\14CSUM_IP6_SCTP" \
717     "\15CSUM_IP6_TSO\16CSUM_IP6_ISCSI\17CSUM_INNER_IP\20CSUM_INNER_IP_UDP" \
718     "\21CSUM_INNER_IP_TCP\22CSUM_INNER_IP_TSO\23CSUM_ENCAP_VXLAN" \
719     "\24CSUM_ENCAP_RSVD1\25CSUM_INNER_L3_CALC\26CSUM_INNER_L3_VALID" \
720     "\27CSUM_INNER_L4_CALC\30CSUM_INNER_L4_VALID\31CSUM_L3_CALC" \
721     "\32CSUM_L3_VALID\33CSUM_L4_CALC\34CSUM_L4_VALID\35CSUM_L5_CALC" \
722     "\36CSUM_L5_VALID\37CSUM_COALESCED\40CSUM_SND_TAG"
723 
724 /* CSUM flags compatibility mappings. */
725 #define	CSUM_IP_CHECKED		CSUM_L3_CALC
726 #define	CSUM_IP_VALID		CSUM_L3_VALID
727 #define	CSUM_DATA_VALID		CSUM_L4_VALID
728 #define	CSUM_PSEUDO_HDR		CSUM_L4_CALC
729 #define	CSUM_SCTP_VALID		CSUM_L4_VALID
730 #define	CSUM_DELAY_DATA		(CSUM_TCP|CSUM_UDP)
731 #define	CSUM_DELAY_IP		CSUM_IP		/* Only v4, no v6 IP hdr csum */
732 #define	CSUM_DELAY_DATA_IPV6	(CSUM_TCP_IPV6|CSUM_UDP_IPV6)
733 #define	CSUM_DATA_VALID_IPV6	CSUM_DATA_VALID
734 #define	CSUM_TCP		CSUM_IP_TCP
735 #define	CSUM_UDP		CSUM_IP_UDP
736 #define	CSUM_SCTP		CSUM_IP_SCTP
737 #define	CSUM_TSO		(CSUM_IP_TSO|CSUM_IP6_TSO)
738 #define	CSUM_INNER_TSO		(CSUM_INNER_IP_TSO|CSUM_INNER_IP6_TSO)
739 #define	CSUM_UDP_IPV6		CSUM_IP6_UDP
740 #define	CSUM_TCP_IPV6		CSUM_IP6_TCP
741 #define	CSUM_SCTP_IPV6		CSUM_IP6_SCTP
742 #define	CSUM_TLS_MASK		(CSUM_L5_CALC|CSUM_L5_VALID)
743 #define	CSUM_TLS_DECRYPTED	CSUM_L5_CALC
744 
745 /*
746  * mbuf types describing the content of the mbuf (including external storage).
747  */
748 #define	MT_NOTMBUF	0	/* USED INTERNALLY ONLY! Object is not mbuf */
749 #define	MT_DATA		1	/* dynamic (data) allocation */
750 #define	MT_HEADER	MT_DATA	/* packet header, use M_PKTHDR instead */
751 
752 #define	MT_VENDOR1	4	/* for vendor-internal use */
753 #define	MT_VENDOR2	5	/* for vendor-internal use */
754 #define	MT_VENDOR3	6	/* for vendor-internal use */
755 #define	MT_VENDOR4	7	/* for vendor-internal use */
756 
757 #define	MT_SONAME	8	/* socket name */
758 
759 #define	MT_EXP1		9	/* for experimental use */
760 #define	MT_EXP2		10	/* for experimental use */
761 #define	MT_EXP3		11	/* for experimental use */
762 #define	MT_EXP4		12	/* for experimental use */
763 
764 #define	MT_CONTROL	14	/* extra-data protocol message */
765 #define	MT_EXTCONTROL	15	/* control message with externalized contents */
766 #define	MT_OOBDATA	16	/* expedited data  */
767 
768 #define	MT_NOINIT	255	/* Not a type but a flag to allocate
769 				   a non-initialized mbuf */
770 
771 /*
772  * String names of mbuf-related UMA(9) and malloc(9) types.  Exposed to
773  * !_KERNEL so that monitoring tools can look up the zones with
774  * libmemstat(3).
775  */
776 #define	MBUF_MEM_NAME		"mbuf"
777 #define	MBUF_CLUSTER_MEM_NAME	"mbuf_cluster"
778 #define	MBUF_PACKET_MEM_NAME	"mbuf_packet"
779 #define	MBUF_JUMBOP_MEM_NAME	"mbuf_jumbo_page"
780 #define	MBUF_JUMBO9_MEM_NAME	"mbuf_jumbo_9k"
781 #define	MBUF_JUMBO16_MEM_NAME	"mbuf_jumbo_16k"
782 #define	MBUF_TAG_MEM_NAME	"mbuf_tag"
783 #define	MBUF_EXTREFCNT_MEM_NAME	"mbuf_ext_refcnt"
784 #define	MBUF_EXTPGS_MEM_NAME	"mbuf_extpgs"
785 
786 #ifdef _KERNEL
787 union if_snd_tag_alloc_params;
788 
789 #define	MBUF_CHECKSLEEP(how) do {					\
790 	if (how == M_WAITOK)						\
791 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,		\
792 		    "Sleeping in \"%s\"", __func__);			\
793 } while (0)
794 
795 /*
796  * Network buffer allocation API
797  *
798  * The rest of it is defined in kern/kern_mbuf.c
799  */
800 extern uma_zone_t	zone_mbuf;
801 extern uma_zone_t	zone_clust;
802 extern uma_zone_t	zone_pack;
803 extern uma_zone_t	zone_jumbop;
804 extern uma_zone_t	zone_jumbo9;
805 extern uma_zone_t	zone_jumbo16;
806 extern uma_zone_t	zone_extpgs;
807 
808 void		 mb_dupcl(struct mbuf *, struct mbuf *);
809 void		 mb_free_ext(struct mbuf *);
810 void		 mb_free_extpg(struct mbuf *);
811 void		 mb_free_mext_pgs(struct mbuf *);
812 struct mbuf	*mb_alloc_ext_pgs(int, m_ext_free_t);
813 struct mbuf	*mb_alloc_ext_plus_pages(int, int);
814 struct mbuf	*mb_mapped_to_unmapped(struct mbuf *, int, int, int,
815 		    struct mbuf **);
816 int		 mb_unmapped_compress(struct mbuf *m);
817 struct mbuf 	*mb_unmapped_to_ext(struct mbuf *m);
818 void		 mb_free_notready(struct mbuf *m, int count);
819 void		 m_adj(struct mbuf *, int);
820 void		 m_adj_decap(struct mbuf *, int);
821 int		 m_apply(struct mbuf *, int, int,
822 		    int (*)(void *, void *, u_int), void *);
823 int		 m_append(struct mbuf *, int, c_caddr_t);
824 void		 m_cat(struct mbuf *, struct mbuf *);
825 void		 m_catpkt(struct mbuf *, struct mbuf *);
826 int		 m_clget(struct mbuf *m, int how);
827 void 		*m_cljget(struct mbuf *m, int how, int size);
828 struct mbuf	*m_collapse(struct mbuf *, int, int);
829 void		 m_copyback(struct mbuf *, int, int, c_caddr_t);
830 void		 m_copydata(const struct mbuf *, int, int, caddr_t);
831 struct mbuf	*m_copym(struct mbuf *, int, int, int);
832 struct mbuf	*m_copypacket(struct mbuf *, int);
833 void		 m_copy_pkthdr(struct mbuf *, struct mbuf *);
834 struct mbuf	*m_copyup(struct mbuf *, int, int);
835 struct mbuf	*m_defrag(struct mbuf *, int);
836 void		 m_demote_pkthdr(struct mbuf *);
837 void		 m_demote(struct mbuf *, int, int);
838 struct mbuf	*m_devget(char *, int, int, struct ifnet *,
839 		    void (*)(char *, caddr_t, u_int));
840 void		 m_dispose_extcontrolm(struct mbuf *m);
841 struct mbuf	*m_dup(const struct mbuf *, int);
842 int		 m_dup_pkthdr(struct mbuf *, const struct mbuf *, int);
843 void		 m_extadd(struct mbuf *, char *, u_int, m_ext_free_t,
844 		    void *, void *, int, int);
845 u_int		 m_fixhdr(struct mbuf *);
846 struct mbuf	*m_fragment(struct mbuf *, int, int);
847 void		 m_freem(struct mbuf *);
848 void		 m_free_raw(struct mbuf *);
849 struct mbuf	*m_get2(int, int, short, int);
850 struct mbuf	*m_get3(int, int, short, int);
851 struct mbuf	*m_getjcl(int, short, int, int);
852 struct mbuf	*m_getm2(struct mbuf *, int, int, short, int);
853 struct mbuf	*m_getptr(struct mbuf *, int, int *);
854 u_int		 m_length(struct mbuf *, struct mbuf **);
855 int		 m_mbuftouio(struct uio *, const struct mbuf *, int);
856 void		 m_move_pkthdr(struct mbuf *, struct mbuf *);
857 int		 m_pkthdr_init(struct mbuf *, int);
858 struct mbuf	*m_prepend(struct mbuf *, int, int);
859 void		 m_print(const struct mbuf *, int);
860 struct mbuf	*m_pulldown(struct mbuf *, int, int, int *);
861 struct mbuf	*m_pullup(struct mbuf *, int);
862 int		 m_sanity(struct mbuf *, int);
863 struct mbuf	*m_split(struct mbuf *, int, int);
864 struct mbuf	*m_uiotombuf(struct uio *, int, int, int, int);
865 int		 m_unmapped_uiomove(const struct mbuf *, int, struct uio *,
866 		    int);
867 struct mbuf	*m_unshare(struct mbuf *, int);
868 int		 m_snd_tag_alloc(struct ifnet *,
869 		    union if_snd_tag_alloc_params *, struct m_snd_tag **);
870 void		 m_snd_tag_init(struct m_snd_tag *, struct ifnet *,
871 		    const struct if_snd_tag_sw *);
872 void		 m_snd_tag_destroy(struct m_snd_tag *);
873 void		 m_rcvif_serialize(struct mbuf *);
874 struct ifnet	*m_rcvif_restore(struct mbuf *);
875 
876 static __inline int
877 m_gettype(int size)
878 {
879 	int type;
880 
881 	switch (size) {
882 	case MSIZE:
883 		type = EXT_MBUF;
884 		break;
885 	case MCLBYTES:
886 		type = EXT_CLUSTER;
887 		break;
888 	case MJUMPAGESIZE:
889 		type = EXT_JUMBOP;
890 		break;
891 	case MJUM9BYTES:
892 		type = EXT_JUMBO9;
893 		break;
894 	case MJUM16BYTES:
895 		type = EXT_JUMBO16;
896 		break;
897 	default:
898 		panic("%s: invalid cluster size %d", __func__, size);
899 	}
900 
901 	return (type);
902 }
903 
904 /*
905  * Associated an external reference counted buffer with an mbuf.
906  */
907 static __inline void
908 m_extaddref(struct mbuf *m, char *buf, u_int size, u_int *ref_cnt,
909     m_ext_free_t freef, void *arg1, void *arg2)
910 {
911 
912 	KASSERT(ref_cnt != NULL, ("%s: ref_cnt not provided", __func__));
913 
914 	atomic_add_int(ref_cnt, 1);
915 	m->m_flags |= M_EXT;
916 	m->m_ext.ext_buf = buf;
917 	m->m_ext.ext_cnt = ref_cnt;
918 	m->m_data = m->m_ext.ext_buf;
919 	m->m_ext.ext_size = size;
920 	m->m_ext.ext_free = freef;
921 	m->m_ext.ext_arg1 = arg1;
922 	m->m_ext.ext_arg2 = arg2;
923 	m->m_ext.ext_type = EXT_EXTREF;
924 	m->m_ext.ext_flags = 0;
925 }
926 
927 static __inline uma_zone_t
928 m_getzone(int size)
929 {
930 	uma_zone_t zone;
931 
932 	switch (size) {
933 	case MCLBYTES:
934 		zone = zone_clust;
935 		break;
936 	case MJUMPAGESIZE:
937 		zone = zone_jumbop;
938 		break;
939 	case MJUM9BYTES:
940 		zone = zone_jumbo9;
941 		break;
942 	case MJUM16BYTES:
943 		zone = zone_jumbo16;
944 		break;
945 	default:
946 		panic("%s: invalid cluster size %d", __func__, size);
947 	}
948 
949 	return (zone);
950 }
951 
952 /*
953  * Initialize an mbuf with linear storage.
954  *
955  * Inline because the consumer text overhead will be roughly the same to
956  * initialize or call a function with this many parameters and M_PKTHDR
957  * should go away with constant propagation for !MGETHDR.
958  */
959 static __inline int
960 m_init(struct mbuf *m, int how, short type, int flags)
961 {
962 	int error;
963 
964 	m->m_next = NULL;
965 	m->m_nextpkt = NULL;
966 	m->m_data = m->m_dat;
967 	m->m_len = 0;
968 	m->m_flags = flags;
969 	m->m_type = type;
970 	if (flags & M_PKTHDR)
971 		error = m_pkthdr_init(m, how);
972 	else
973 		error = 0;
974 
975 	MBUF_PROBE5(m__init, m, how, type, flags, error);
976 	return (error);
977 }
978 
979 static __inline struct mbuf *
980 m_get_raw(int how, short type)
981 {
982 	struct mbuf *m;
983 	struct mb_args args;
984 
985 	args.flags = 0;
986 	args.type = type | MT_NOINIT;
987 	m = uma_zalloc_arg(zone_mbuf, &args, how);
988 	MBUF_PROBE3(m__get_raw, how, type, m);
989 	return (m);
990 }
991 
992 static __inline struct mbuf *
993 m_get(int how, short type)
994 {
995 	struct mbuf *m;
996 	struct mb_args args;
997 
998 	args.flags = 0;
999 	args.type = type;
1000 	m = uma_zalloc_arg(zone_mbuf, &args, how);
1001 	MBUF_PROBE3(m__get, how, type, m);
1002 	return (m);
1003 }
1004 
1005 static __inline struct mbuf *
1006 m_gethdr_raw(int how, short type)
1007 {
1008 	struct mbuf *m;
1009 	struct mb_args args;
1010 
1011 	args.flags = M_PKTHDR;
1012 	args.type = type | MT_NOINIT;
1013 	m = uma_zalloc_arg(zone_mbuf, &args, how);
1014 	MBUF_PROBE3(m__gethdr_raw, how, type, m);
1015 	return (m);
1016 }
1017 
1018 static __inline struct mbuf *
1019 m_gethdr(int how, short type)
1020 {
1021 	struct mbuf *m;
1022 	struct mb_args args;
1023 
1024 	args.flags = M_PKTHDR;
1025 	args.type = type;
1026 	m = uma_zalloc_arg(zone_mbuf, &args, how);
1027 	MBUF_PROBE3(m__gethdr, how, type, m);
1028 	return (m);
1029 }
1030 
1031 static __inline struct mbuf *
1032 m_getcl(int how, short type, int flags)
1033 {
1034 	struct mbuf *m;
1035 	struct mb_args args;
1036 
1037 	args.flags = flags;
1038 	args.type = type;
1039 	m = uma_zalloc_arg(zone_pack, &args, how);
1040 	MBUF_PROBE4(m__getcl, how, type, flags, m);
1041 	return (m);
1042 }
1043 
1044 /*
1045  * XXX: m_cljset() is a dangerous API.  One must attach only a new,
1046  * unreferenced cluster to an mbuf(9).  It is not possible to assert
1047  * that, so care can be taken only by users of the API.
1048  */
1049 static __inline void
1050 m_cljset(struct mbuf *m, void *cl, int type)
1051 {
1052 	int size;
1053 
1054 	switch (type) {
1055 	case EXT_CLUSTER:
1056 		size = MCLBYTES;
1057 		break;
1058 	case EXT_JUMBOP:
1059 		size = MJUMPAGESIZE;
1060 		break;
1061 	case EXT_JUMBO9:
1062 		size = MJUM9BYTES;
1063 		break;
1064 	case EXT_JUMBO16:
1065 		size = MJUM16BYTES;
1066 		break;
1067 	default:
1068 		panic("%s: unknown cluster type %d", __func__, type);
1069 		break;
1070 	}
1071 
1072 	m->m_data = m->m_ext.ext_buf = cl;
1073 	m->m_ext.ext_free = m->m_ext.ext_arg1 = m->m_ext.ext_arg2 = NULL;
1074 	m->m_ext.ext_size = size;
1075 	m->m_ext.ext_type = type;
1076 	m->m_ext.ext_flags = EXT_FLAG_EMBREF;
1077 	m->m_ext.ext_count = 1;
1078 	m->m_flags |= M_EXT;
1079 	MBUF_PROBE3(m__cljset, m, cl, type);
1080 }
1081 
1082 static __inline void
1083 m_chtype(struct mbuf *m, short new_type)
1084 {
1085 
1086 	m->m_type = new_type;
1087 }
1088 
1089 static __inline void
1090 m_clrprotoflags(struct mbuf *m)
1091 {
1092 
1093 	while (m) {
1094 		m->m_flags &= ~M_PROTOFLAGS;
1095 		m = m->m_next;
1096 	}
1097 }
1098 
1099 static __inline struct mbuf *
1100 m_last(struct mbuf *m)
1101 {
1102 
1103 	while (m->m_next)
1104 		m = m->m_next;
1105 	return (m);
1106 }
1107 
1108 static inline u_int
1109 m_extrefcnt(struct mbuf *m)
1110 {
1111 
1112 	KASSERT(m->m_flags & M_EXT, ("%s: M_EXT missing", __func__));
1113 
1114 	return ((m->m_ext.ext_flags & EXT_FLAG_EMBREF) ? m->m_ext.ext_count :
1115 	    *m->m_ext.ext_cnt);
1116 }
1117 
1118 /*
1119  * mbuf, cluster, and external object allocation macros (for compatibility
1120  * purposes).
1121  */
1122 #define	M_MOVE_PKTHDR(to, from)	m_move_pkthdr((to), (from))
1123 #define	MGET(m, how, type)	((m) = m_get((how), (type)))
1124 #define	MGETHDR(m, how, type)	((m) = m_gethdr((how), (type)))
1125 #define	MCLGET(m, how)		m_clget((m), (how))
1126 #define	MEXTADD(m, buf, size, free, arg1, arg2, flags, type)		\
1127     m_extadd((m), (char *)(buf), (size), (free), (arg1), (arg2),	\
1128     (flags), (type))
1129 #define	m_getm(m, len, how, type)					\
1130     m_getm2((m), (len), (how), (type), M_PKTHDR)
1131 
1132 /*
1133  * Evaluate TRUE if it's safe to write to the mbuf m's data region (this can
1134  * be both the local data payload, or an external buffer area, depending on
1135  * whether M_EXT is set).
1136  */
1137 #define	M_WRITABLE(m)	(((m)->m_flags & (M_RDONLY | M_EXTPG)) == 0 &&	\
1138 			 (!(((m)->m_flags & M_EXT)) ||			\
1139 			 (m_extrefcnt(m) == 1)))
1140 
1141 /* Check if the supplied mbuf has a packet header, or else panic. */
1142 #define	M_ASSERTPKTHDR(m)						\
1143 	KASSERT((m) != NULL && (m)->m_flags & M_PKTHDR,			\
1144 	    ("%s: no mbuf packet header!", __func__))
1145 
1146 /* Check if the supplied mbuf has no send tag, or else panic. */
1147 #define	M_ASSERT_NO_SND_TAG(m)						\
1148 	KASSERT((m) != NULL && (m)->m_flags & M_PKTHDR &&		\
1149 	       ((m)->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0,		\
1150 	    ("%s: receive mbuf has send tag!", __func__))
1151 
1152 /* Check if mbuf is multipage. */
1153 #define M_ASSERTEXTPG(m)						\
1154 	KASSERT(((m)->m_flags & (M_EXTPG|M_PKTHDR)) == M_EXTPG,		\
1155 	    ("%s: m %p is not multipage!", __func__, m))
1156 
1157 /*
1158  * Ensure that the supplied mbuf is a valid, non-free mbuf.
1159  *
1160  * XXX: Broken at the moment.  Need some UMA magic to make it work again.
1161  */
1162 #define	M_ASSERTVALID(m)						\
1163 	KASSERT((((struct mbuf *)m)->m_flags & 0) == 0,			\
1164 	    ("%s: attempted use of a free mbuf!", __func__))
1165 
1166 /* Check whether any mbuf in the chain is unmapped. */
1167 #ifdef INVARIANTS
1168 #define	M_ASSERTMAPPED(m) do {						\
1169 	for (struct mbuf *__m = (m); __m != NULL; __m = __m->m_next)	\
1170 		KASSERT((__m->m_flags & M_EXTPG) == 0,			\
1171 		    ("%s: chain %p contains an unmapped mbuf", __func__, (m)));\
1172 } while (0)
1173 #else
1174 #define	M_ASSERTMAPPED(m) do {} while (0)
1175 #endif
1176 
1177 /*
1178  * Return the address of the start of the buffer associated with an mbuf,
1179  * handling external storage, packet-header mbufs, and regular data mbufs.
1180  */
1181 #define	M_START(m)							\
1182 	(((m)->m_flags & M_EXTPG) ? NULL :				\
1183 	 ((m)->m_flags & M_EXT) ? (m)->m_ext.ext_buf :			\
1184 	 ((m)->m_flags & M_PKTHDR) ? &(m)->m_pktdat[0] :		\
1185 	 &(m)->m_dat[0])
1186 
1187 /*
1188  * Return the size of the buffer associated with an mbuf, handling external
1189  * storage, packet-header mbufs, and regular data mbufs.
1190  */
1191 #define	M_SIZE(m)							\
1192 	(((m)->m_flags & M_EXT) ? (m)->m_ext.ext_size :			\
1193 	 ((m)->m_flags & M_PKTHDR) ? MHLEN :				\
1194 	 MLEN)
1195 
1196 /*
1197  * Set the m_data pointer of a newly allocated mbuf to place an object of the
1198  * specified size at the end of the mbuf, longword aligned.
1199  *
1200  * NB: Historically, we had M_ALIGN(), MH_ALIGN(), and MEXT_ALIGN() as
1201  * separate macros, each asserting that it was called at the proper moment.
1202  * This required callers to themselves test the storage type and call the
1203  * right one.  Rather than require callers to be aware of those layout
1204  * decisions, we centralize here.
1205  */
1206 static __inline void
1207 m_align(struct mbuf *m, int len)
1208 {
1209 #ifdef INVARIANTS
1210 	const char *msg = "%s: not a virgin mbuf";
1211 #endif
1212 	int adjust;
1213 
1214 	KASSERT(m->m_data == M_START(m), (msg, __func__));
1215 
1216 	adjust = M_SIZE(m) - len;
1217 	m->m_data += adjust &~ (sizeof(long)-1);
1218 }
1219 
1220 #define	M_ALIGN(m, len)		m_align(m, len)
1221 #define	MH_ALIGN(m, len)	m_align(m, len)
1222 #define	MEXT_ALIGN(m, len)	m_align(m, len)
1223 
1224 /*
1225  * Compute the amount of space available before the current start of data in
1226  * an mbuf.
1227  *
1228  * The M_WRITABLE() is a temporary, conservative safety measure: the burden
1229  * of checking writability of the mbuf data area rests solely with the caller.
1230  *
1231  * NB: In previous versions, M_LEADINGSPACE() would only check M_WRITABLE()
1232  * for mbufs with external storage.  We now allow mbuf-embedded data to be
1233  * read-only as well.
1234  */
1235 #define	M_LEADINGSPACE(m)						\
1236 	(M_WRITABLE(m) ? ((m)->m_data - M_START(m)) : 0)
1237 
1238 /*
1239  * So M_TRAILINGROOM() is for when you want to know how much space
1240  * would be there if it was writable. This can be used to
1241  * detect changes in mbufs by knowing the value at one point
1242  * and then being able to compare it later to the current M_TRAILINGROOM().
1243  * The TRAILINGSPACE() macro is not suitable for this since an mbuf
1244  * at one point might not be writable and then later it becomes writable
1245  * even though the space at the back of it has not changed.
1246  */
1247 #define M_TRAILINGROOM(m) ((M_START(m) + M_SIZE(m)) - ((m)->m_data + (m)->m_len))
1248 /*
1249  * Compute the amount of space available after the end of data in an mbuf.
1250  *
1251  * The M_WRITABLE() is a temporary, conservative safety measure: the burden
1252  * of checking writability of the mbuf data area rests solely with the caller.
1253  *
1254  * NB: In previous versions, M_TRAILINGSPACE() would only check M_WRITABLE()
1255  * for mbufs with external storage.  We now allow mbuf-embedded data to be
1256  * read-only as well.
1257  */
1258 #define	M_TRAILINGSPACE(m) (M_WRITABLE(m) ? M_TRAILINGROOM(m) : 0)
1259 
1260 /*
1261  * Arrange to prepend space of size plen to mbuf m.  If a new mbuf must be
1262  * allocated, how specifies whether to wait.  If the allocation fails, the
1263  * original mbuf chain is freed and m is set to NULL.
1264  */
1265 #define	M_PREPEND(m, plen, how) do {					\
1266 	struct mbuf **_mmp = &(m);					\
1267 	struct mbuf *_mm = *_mmp;					\
1268 	int _mplen = (plen);						\
1269 	int __mhow = (how);						\
1270 									\
1271 	MBUF_CHECKSLEEP(how);						\
1272 	if (M_LEADINGSPACE(_mm) >= _mplen) {				\
1273 		_mm->m_data -= _mplen;					\
1274 		_mm->m_len += _mplen;					\
1275 	} else								\
1276 		_mm = m_prepend(_mm, _mplen, __mhow);			\
1277 	if (_mm != NULL && _mm->m_flags & M_PKTHDR)			\
1278 		_mm->m_pkthdr.len += _mplen;				\
1279 	*_mmp = _mm;							\
1280 } while (0)
1281 
1282 /*
1283  * Change mbuf to new type.  This is a relatively expensive operation and
1284  * should be avoided.
1285  */
1286 #define	MCHTYPE(m, t)	m_chtype((m), (t))
1287 
1288 /* Return the rcvif of a packet header. */
1289 static __inline struct ifnet *
1290 m_rcvif(struct mbuf *m)
1291 {
1292 
1293 	M_ASSERTPKTHDR(m);
1294 	if (m->m_pkthdr.csum_flags & CSUM_SND_TAG)
1295 		return (NULL);
1296 	return (m->m_pkthdr.rcvif);
1297 }
1298 
1299 /* Length to m_copy to copy all. */
1300 #define	M_COPYALL	1000000000
1301 
1302 extern u_int		max_linkhdr;	/* Largest link-level header */
1303 extern u_int		max_hdr;	/* Largest link + protocol header */
1304 extern u_int		max_protohdr;	/* Largest protocol header */
1305 void max_linkhdr_grow(u_int);
1306 void max_protohdr_grow(u_int);
1307 
1308 extern int		nmbclusters;	/* Maximum number of clusters */
1309 extern bool		mb_use_ext_pgs;	/* Use ext_pgs for sendfile */
1310 
1311 /*-
1312  * Network packets may have annotations attached by affixing a list of
1313  * "packet tags" to the pkthdr structure.  Packet tags are dynamically
1314  * allocated semi-opaque data structures that have a fixed header
1315  * (struct m_tag) that specifies the size of the memory block and a
1316  * <cookie,type> pair that identifies it.  The cookie is a 32-bit unique
1317  * unsigned value used to identify a module or ABI.  By convention this value
1318  * is chosen as the date+time that the module is created, expressed as the
1319  * number of seconds since the epoch (e.g., using date -u +'%s').  The type
1320  * value is an ABI/module-specific value that identifies a particular
1321  * annotation and is private to the module.  For compatibility with systems
1322  * like OpenBSD that define packet tags w/o an ABI/module cookie, the value
1323  * PACKET_ABI_COMPAT is used to implement m_tag_get and m_tag_find
1324  * compatibility shim functions and several tag types are defined below.
1325  * Users that do not require compatibility should use a private cookie value
1326  * so that packet tag-related definitions can be maintained privately.
1327  *
1328  * Note that the packet tag returned by m_tag_alloc has the default memory
1329  * alignment implemented by malloc.  To reference private data one can use a
1330  * construct like:
1331  *
1332  *	struct m_tag *mtag = m_tag_alloc(...);
1333  *	struct foo *p = (struct foo *)(mtag+1);
1334  *
1335  * if the alignment of struct m_tag is sufficient for referencing members of
1336  * struct foo.  Otherwise it is necessary to embed struct m_tag within the
1337  * private data structure to insure proper alignment; e.g.,
1338  *
1339  *	struct foo {
1340  *		struct m_tag	tag;
1341  *		...
1342  *	};
1343  *	struct foo *p = (struct foo *) m_tag_alloc(...);
1344  *	struct m_tag *mtag = &p->tag;
1345  */
1346 
1347 /*
1348  * Persistent tags stay with an mbuf until the mbuf is reclaimed.  Otherwise
1349  * tags are expected to ``vanish'' when they pass through a network
1350  * interface.  For most interfaces this happens normally as the tags are
1351  * reclaimed when the mbuf is free'd.  However in some special cases
1352  * reclaiming must be done manually.  An example is packets that pass through
1353  * the loopback interface.  Also, one must be careful to do this when
1354  * ``turning around'' packets (e.g., icmp_reflect).
1355  *
1356  * To mark a tag persistent bit-or this flag in when defining the tag id.
1357  * The tag will then be treated as described above.
1358  */
1359 #define	MTAG_PERSISTENT				0x800
1360 
1361 #define	PACKET_TAG_NONE				0  /* Nadda */
1362 
1363 /* Packet tags for use with PACKET_ABI_COMPAT. */
1364 #define	PACKET_TAG_IPSEC_IN_DONE		1  /* IPsec applied, in */
1365 #define	PACKET_TAG_IPSEC_OUT_DONE		2  /* IPsec applied, out */
1366 #define	PACKET_TAG_IPSEC_IN_CRYPTO_DONE		3  /* NIC IPsec crypto done */
1367 #define	PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED	4  /* NIC IPsec crypto req'ed */
1368 #define	PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO	5  /* NIC notifies IPsec */
1369 #define	PACKET_TAG_IPSEC_PENDING_TDB		6  /* Reminder to do IPsec */
1370 #define	PACKET_TAG_BRIDGE			7  /* Bridge processing done */
1371 #define	PACKET_TAG_GIF				8  /* GIF processing done */
1372 #define	PACKET_TAG_GRE				9  /* GRE processing done */
1373 #define	PACKET_TAG_IN_PACKET_CHECKSUM		10 /* NIC checksumming done */
1374 #define	PACKET_TAG_ENCAP			11 /* Encap.  processing */
1375 #define	PACKET_TAG_IPSEC_SOCKET			12 /* IPSEC socket ref */
1376 #define	PACKET_TAG_IPSEC_HISTORY		13 /* IPSEC history */
1377 #define	PACKET_TAG_IPV6_INPUT			14 /* IPV6 input processing */
1378 #define	PACKET_TAG_DUMMYNET			15 /* dummynet info */
1379 #define	PACKET_TAG_DIVERT			17 /* divert info */
1380 #define	PACKET_TAG_IPFORWARD			18 /* ipforward info */
1381 #define	PACKET_TAG_MACLABEL	(19 | MTAG_PERSISTENT) /* MAC label */
1382 #define	PACKET_TAG_PF				21 /* PF/ALTQ information */
1383 /* was	PACKET_TAG_RTSOCKFAM			25    rtsock sa family */
1384 #define	PACKET_TAG_IPOPTIONS			27 /* Saved IP options */
1385 #define	PACKET_TAG_CARP				28 /* CARP info */
1386 #define	PACKET_TAG_IPSEC_NAT_T_PORTS		29 /* two uint16_t */
1387 #define	PACKET_TAG_ND_OUTGOING			30 /* ND outgoing */
1388 #define	PACKET_TAG_PF_REASSEMBLED		31
1389 
1390 /* Specific cookies and tags. */
1391 
1392 /* Packet tag routines. */
1393 struct m_tag	*m_tag_alloc(uint32_t, uint16_t, int, int);
1394 void		 m_tag_delete(struct mbuf *, struct m_tag *);
1395 void		 m_tag_delete_chain(struct mbuf *, struct m_tag *);
1396 void		 m_tag_free_default(struct m_tag *);
1397 struct m_tag	*m_tag_locate(struct mbuf *, uint32_t, uint16_t,
1398     struct m_tag *);
1399 struct m_tag	*m_tag_copy(struct m_tag *, int);
1400 int		 m_tag_copy_chain(struct mbuf *, const struct mbuf *, int);
1401 void		 m_tag_delete_nonpersistent(struct mbuf *);
1402 
1403 /*
1404  * Initialize the list of tags associated with an mbuf.
1405  */
1406 static __inline void
1407 m_tag_init(struct mbuf *m)
1408 {
1409 
1410 	SLIST_INIT(&m->m_pkthdr.tags);
1411 }
1412 
1413 /*
1414  * Set up the contents of a tag.  Note that this does not fill in the free
1415  * method; the caller is expected to do that.
1416  *
1417  * XXX probably should be called m_tag_init, but that was already taken.
1418  */
1419 static __inline void
1420 m_tag_setup(struct m_tag *t, uint32_t cookie, uint16_t type, int len)
1421 {
1422 
1423 	t->m_tag_id = type;
1424 	t->m_tag_len = len;
1425 	t->m_tag_cookie = cookie;
1426 }
1427 
1428 /*
1429  * Reclaim resources associated with a tag.
1430  */
1431 static __inline void
1432 m_tag_free(struct m_tag *t)
1433 {
1434 
1435 	(*t->m_tag_free)(t);
1436 }
1437 
1438 /*
1439  * Return the first tag associated with an mbuf.
1440  */
1441 static __inline struct m_tag *
1442 m_tag_first(struct mbuf *m)
1443 {
1444 
1445 	return (SLIST_FIRST(&m->m_pkthdr.tags));
1446 }
1447 
1448 /*
1449  * Return the next tag in the list of tags associated with an mbuf.
1450  */
1451 static __inline struct m_tag *
1452 m_tag_next(struct mbuf *m __unused, struct m_tag *t)
1453 {
1454 
1455 	return (SLIST_NEXT(t, m_tag_link));
1456 }
1457 
1458 /*
1459  * Prepend a tag to the list of tags associated with an mbuf.
1460  */
1461 static __inline void
1462 m_tag_prepend(struct mbuf *m, struct m_tag *t)
1463 {
1464 
1465 	SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link);
1466 }
1467 
1468 /*
1469  * Unlink a tag from the list of tags associated with an mbuf.
1470  */
1471 static __inline void
1472 m_tag_unlink(struct mbuf *m, struct m_tag *t)
1473 {
1474 
1475 	SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link);
1476 }
1477 
1478 /* These are for OpenBSD compatibility. */
1479 #define	MTAG_ABI_COMPAT		0		/* compatibility ABI */
1480 
1481 static __inline struct m_tag *
1482 m_tag_get(uint16_t type, int length, int wait)
1483 {
1484 	return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait));
1485 }
1486 
1487 static __inline struct m_tag *
1488 m_tag_find(struct mbuf *m, uint16_t type, struct m_tag *start)
1489 {
1490 	return (SLIST_EMPTY(&m->m_pkthdr.tags) ? (struct m_tag *)NULL :
1491 	    m_tag_locate(m, MTAG_ABI_COMPAT, type, start));
1492 }
1493 
1494 static inline struct m_snd_tag *
1495 m_snd_tag_ref(struct m_snd_tag *mst)
1496 {
1497 
1498 	refcount_acquire(&mst->refcount);
1499 	return (mst);
1500 }
1501 
1502 static inline void
1503 m_snd_tag_rele(struct m_snd_tag *mst)
1504 {
1505 
1506 	if (refcount_release(&mst->refcount))
1507 		m_snd_tag_destroy(mst);
1508 }
1509 
1510 static __inline struct mbuf *
1511 m_free(struct mbuf *m)
1512 {
1513 	struct mbuf *n = m->m_next;
1514 
1515 	MBUF_PROBE1(m__free, m);
1516 	if ((m->m_flags & (M_PKTHDR|M_NOFREE)) == (M_PKTHDR|M_NOFREE))
1517 		m_tag_delete_chain(m, NULL);
1518 	if (m->m_flags & M_PKTHDR && m->m_pkthdr.csum_flags & CSUM_SND_TAG)
1519 		m_snd_tag_rele(m->m_pkthdr.snd_tag);
1520 	if (m->m_flags & M_EXTPG)
1521 		mb_free_extpg(m);
1522 	else if (m->m_flags & M_EXT)
1523 		mb_free_ext(m);
1524 	else if ((m->m_flags & M_NOFREE) == 0)
1525 		uma_zfree(zone_mbuf, m);
1526 	return (n);
1527 }
1528 
1529 static __inline int
1530 rt_m_getfib(struct mbuf *m)
1531 {
1532 	KASSERT(m->m_flags & M_PKTHDR , ("Attempt to get FIB from non header mbuf."));
1533 	return (m->m_pkthdr.fibnum);
1534 }
1535 
1536 #define M_GETFIB(_m)   rt_m_getfib(_m)
1537 
1538 #define M_SETFIB(_m, _fib) do {						\
1539         KASSERT((_m)->m_flags & M_PKTHDR, ("Attempt to set FIB on non header mbuf."));	\
1540 	((_m)->m_pkthdr.fibnum) = (_fib);				\
1541 } while (0)
1542 
1543 /* flags passed as first argument for "m_xxx_tcpip_hash()" */
1544 #define	MBUF_HASHFLAG_L2	(1 << 2)
1545 #define	MBUF_HASHFLAG_L3	(1 << 3)
1546 #define	MBUF_HASHFLAG_L4	(1 << 4)
1547 
1548 /* mbuf hashing helper routines */
1549 uint32_t	m_ether_tcpip_hash_init(void);
1550 uint32_t	m_ether_tcpip_hash(const uint32_t, const struct mbuf *, uint32_t);
1551 uint32_t	m_infiniband_tcpip_hash_init(void);
1552 uint32_t	m_infiniband_tcpip_hash(const uint32_t, const struct mbuf *, uint32_t);
1553 
1554 #ifdef MBUF_PROFILING
1555  void m_profile(struct mbuf *m);
1556  #define M_PROFILE(m) m_profile(m)
1557 #else
1558  #define M_PROFILE(m)
1559 #endif
1560 
1561 struct mbufq {
1562 	STAILQ_HEAD(, mbuf)	mq_head;
1563 	int			mq_len;
1564 	int			mq_maxlen;
1565 };
1566 
1567 static inline void
1568 mbufq_init(struct mbufq *mq, int maxlen)
1569 {
1570 
1571 	STAILQ_INIT(&mq->mq_head);
1572 	mq->mq_maxlen = maxlen;
1573 	mq->mq_len = 0;
1574 }
1575 
1576 static inline struct mbuf *
1577 mbufq_flush(struct mbufq *mq)
1578 {
1579 	struct mbuf *m;
1580 
1581 	m = STAILQ_FIRST(&mq->mq_head);
1582 	STAILQ_INIT(&mq->mq_head);
1583 	mq->mq_len = 0;
1584 	return (m);
1585 }
1586 
1587 static inline void
1588 mbufq_drain(struct mbufq *mq)
1589 {
1590 	struct mbuf *m, *n;
1591 
1592 	n = mbufq_flush(mq);
1593 	while ((m = n) != NULL) {
1594 		n = STAILQ_NEXT(m, m_stailqpkt);
1595 		m_freem(m);
1596 	}
1597 }
1598 
1599 static inline struct mbuf *
1600 mbufq_first(const struct mbufq *mq)
1601 {
1602 
1603 	return (STAILQ_FIRST(&mq->mq_head));
1604 }
1605 
1606 static inline struct mbuf *
1607 mbufq_last(const struct mbufq *mq)
1608 {
1609 
1610 	return (STAILQ_LAST(&mq->mq_head, mbuf, m_stailqpkt));
1611 }
1612 
1613 static inline int
1614 mbufq_full(const struct mbufq *mq)
1615 {
1616 
1617 	return (mq->mq_maxlen > 0 && mq->mq_len >= mq->mq_maxlen);
1618 }
1619 
1620 static inline int
1621 mbufq_len(const struct mbufq *mq)
1622 {
1623 
1624 	return (mq->mq_len);
1625 }
1626 
1627 static inline int
1628 mbufq_enqueue(struct mbufq *mq, struct mbuf *m)
1629 {
1630 
1631 	if (mbufq_full(mq))
1632 		return (ENOBUFS);
1633 	STAILQ_INSERT_TAIL(&mq->mq_head, m, m_stailqpkt);
1634 	mq->mq_len++;
1635 	return (0);
1636 }
1637 
1638 static inline struct mbuf *
1639 mbufq_dequeue(struct mbufq *mq)
1640 {
1641 	struct mbuf *m;
1642 
1643 	m = STAILQ_FIRST(&mq->mq_head);
1644 	if (m) {
1645 		STAILQ_REMOVE_HEAD(&mq->mq_head, m_stailqpkt);
1646 		m->m_nextpkt = NULL;
1647 		mq->mq_len--;
1648 	}
1649 	return (m);
1650 }
1651 
1652 static inline void
1653 mbufq_prepend(struct mbufq *mq, struct mbuf *m)
1654 {
1655 
1656 	STAILQ_INSERT_HEAD(&mq->mq_head, m, m_stailqpkt);
1657 	mq->mq_len++;
1658 }
1659 
1660 /*
1661  * Note: this doesn't enforce the maximum list size for dst.
1662  */
1663 static inline void
1664 mbufq_concat(struct mbufq *mq_dst, struct mbufq *mq_src)
1665 {
1666 
1667 	mq_dst->mq_len += mq_src->mq_len;
1668 	STAILQ_CONCAT(&mq_dst->mq_head, &mq_src->mq_head);
1669 	mq_src->mq_len = 0;
1670 }
1671 
1672 #ifdef _SYS_TIMESPEC_H_
1673 static inline void
1674 mbuf_tstmp2timespec(struct mbuf *m, struct timespec *ts)
1675 {
1676 
1677 	KASSERT((m->m_flags & M_PKTHDR) != 0, ("mbuf %p no M_PKTHDR", m));
1678 	KASSERT((m->m_flags & (M_TSTMP|M_TSTMP_LRO)) != 0,
1679 	    ("mbuf %p no M_TSTMP or M_TSTMP_LRO", m));
1680 	ts->tv_sec = m->m_pkthdr.rcv_tstmp / 1000000000;
1681 	ts->tv_nsec = m->m_pkthdr.rcv_tstmp % 1000000000;
1682 }
1683 #endif
1684 
1685 static inline void
1686 mbuf_tstmp2timeval(struct mbuf *m, struct timeval *tv)
1687 {
1688 
1689 	KASSERT((m->m_flags & M_PKTHDR) != 0, ("mbuf %p no M_PKTHDR", m));
1690 	KASSERT((m->m_flags & (M_TSTMP|M_TSTMP_LRO)) != 0,
1691 	    ("mbuf %p no M_TSTMP or M_TSTMP_LRO", m));
1692 	tv->tv_sec = m->m_pkthdr.rcv_tstmp / 1000000000;
1693 	tv->tv_usec = (m->m_pkthdr.rcv_tstmp % 1000000000) / 1000;
1694 }
1695 
1696 #ifdef DEBUGNET
1697 /* Invoked from the debugnet client code. */
1698 void	debugnet_mbuf_drain(void);
1699 void	debugnet_mbuf_start(void);
1700 void	debugnet_mbuf_finish(void);
1701 void	debugnet_mbuf_reinit(int nmbuf, int nclust, int clsize);
1702 #endif
1703 
1704 static inline bool
1705 mbuf_has_tls_session(struct mbuf *m)
1706 {
1707 
1708 	if (m->m_flags & M_EXTPG) {
1709 		if (m->m_epg_tls != NULL) {
1710 			return (true);
1711 		}
1712 	}
1713 	return (false);
1714 }
1715 
1716 #endif /* _KERNEL */
1717 #endif /* !_SYS_MBUF_H_ */
1718