xref: /freebsd/sys/sys/mbuf.h (revision 2008043f386721d58158e37e0d7e50df8095942d)
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  */
34 
35 #ifndef _SYS_MBUF_H_
36 #define	_SYS_MBUF_H_
37 
38 /* XXX: These includes suck. Sorry! */
39 #include <sys/queue.h>
40 #ifdef _KERNEL
41 #include <sys/systm.h>
42 #include <sys/refcount.h>
43 #include <vm/uma.h>
44 
45 #include <sys/sdt.h>
46 
47 #define	MBUF_PROBE1(probe, arg0)					\
48 	SDT_PROBE1(sdt, , , probe, arg0)
49 #define	MBUF_PROBE2(probe, arg0, arg1)					\
50 	SDT_PROBE2(sdt, , , probe, arg0, arg1)
51 #define	MBUF_PROBE3(probe, arg0, arg1, arg2)				\
52 	SDT_PROBE3(sdt, , , probe, arg0, arg1, arg2)
53 #define	MBUF_PROBE4(probe, arg0, arg1, arg2, arg3)			\
54 	SDT_PROBE4(sdt, , , probe, arg0, arg1, arg2, arg3)
55 #define	MBUF_PROBE5(probe, arg0, arg1, arg2, arg3, arg4)		\
56 	SDT_PROBE5(sdt, , , probe, arg0, arg1, arg2, arg3, arg4)
57 
58 SDT_PROBE_DECLARE(sdt, , , m__init);
59 SDT_PROBE_DECLARE(sdt, , , m__gethdr_raw);
60 SDT_PROBE_DECLARE(sdt, , , m__gethdr);
61 SDT_PROBE_DECLARE(sdt, , , m__get_raw);
62 SDT_PROBE_DECLARE(sdt, , , m__get);
63 SDT_PROBE_DECLARE(sdt, , , m__getcl);
64 SDT_PROBE_DECLARE(sdt, , , m__getjcl);
65 SDT_PROBE_DECLARE(sdt, , , m__clget);
66 SDT_PROBE_DECLARE(sdt, , , m__cljget);
67 SDT_PROBE_DECLARE(sdt, , , m__cljset);
68 SDT_PROBE_DECLARE(sdt, , , m__free);
69 SDT_PROBE_DECLARE(sdt, , , m__freem);
70 
71 #endif /* _KERNEL */
72 
73 /*
74  * Mbufs are of a single size, MSIZE (sys/param.h), which includes overhead.
75  * An mbuf may add a single "mbuf cluster" of size MCLBYTES (also in
76  * sys/param.h), which has no additional overhead and is used instead of the
77  * internal data area; this is done when at least MINCLSIZE of data must be
78  * stored.  Additionally, it is possible to allocate a separate buffer
79  * externally and attach it to the mbuf in a way similar to that of mbuf
80  * clusters.
81  *
82  * NB: These calculation do not take actual compiler-induced alignment and
83  * padding inside the complete struct mbuf into account.  Appropriate
84  * attention is required when changing members of struct mbuf.
85  *
86  * MLEN is data length in a normal mbuf.
87  * MHLEN is data length in an mbuf with pktheader.
88  * MINCLSIZE is a smallest amount of data that should be put into cluster.
89  *
90  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
91  * they are sensible.
92  */
93 struct mbuf;
94 #define	MHSIZE		offsetof(struct mbuf, m_dat)
95 #define	MPKTHSIZE	offsetof(struct mbuf, m_pktdat)
96 #define	MLEN		((int)(MSIZE - MHSIZE))
97 #define	MHLEN		((int)(MSIZE - MPKTHSIZE))
98 #define	MINCLSIZE	(MHLEN + 1)
99 #define	M_NODOM		255
100 
101 #ifdef _KERNEL
102 /*-
103  * Macro for type conversion: convert mbuf pointer to data pointer of correct
104  * type:
105  *
106  * mtod(m, t)	-- Convert mbuf pointer to data pointer of correct type.
107  * mtodo(m, o) -- Same as above but with offset 'o' into data.
108  */
109 #define	mtod(m, t)	((t)((m)->m_data))
110 #define	mtodo(m, o)	((void *)(((m)->m_data) + (o)))
111 
112 /*
113  * Argument structure passed to UMA routines during mbuf and packet
114  * allocations.
115  */
116 struct mb_args {
117 	int	flags;	/* Flags for mbuf being allocated */
118 	short	type;	/* Type of mbuf being allocated */
119 };
120 #endif /* _KERNEL */
121 
122 /*
123  * Packet tag structure (see below for details).
124  */
125 struct m_tag {
126 	SLIST_ENTRY(m_tag)	m_tag_link;	/* List of packet tags */
127 	u_int16_t		m_tag_id;	/* Tag ID */
128 	u_int16_t		m_tag_len;	/* Length of data */
129 	u_int32_t		m_tag_cookie;	/* ABI/Module ID */
130 	void			(*m_tag_free)(struct m_tag *);
131 };
132 
133 /*
134  * Static network interface owned tag.
135  * Allocated through ifp->if_snd_tag_alloc().
136  */
137 struct if_snd_tag_sw;
138 
139 struct m_snd_tag {
140 	struct ifnet *ifp;		/* network interface tag belongs to */
141 	const struct if_snd_tag_sw *sw;
142 	volatile u_int refcount;
143 };
144 
145 /*
146  * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set.
147  * Size ILP32: 56
148  *	 LP64: 64
149  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
150  * they are correct.
151  */
152 struct pkthdr {
153 	union {
154 		struct m_snd_tag *snd_tag;	/* send tag, if any */
155 		struct ifnet	*rcvif;		/* rcv interface */
156 		struct {
157 			uint16_t rcvidx;	/* rcv interface index ... */
158 			uint16_t rcvgen;	/* ... and generation count */
159 		};
160 	};
161 	union {
162 		struct ifnet	*leaf_rcvif;	/* leaf rcv interface */
163 		struct {
164 			uint16_t leaf_rcvidx;	/* leaf rcv interface index ... */
165 			uint16_t leaf_rcvgen;	/* ... and generation count */
166 		};
167 	};
168 	SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */
169 	int32_t		 len;		/* total packet length */
170 
171 	/* Layer crossing persistent information. */
172 	uint32_t	 flowid;	/* packet's 4-tuple system */
173 	uint32_t	 csum_flags;	/* checksum and offload features */
174 	uint16_t	 fibnum;	/* this packet should use this fib */
175 	uint8_t		 numa_domain;	/* NUMA domain of recvd pkt */
176 	uint8_t		 rsstype;	/* hash type */
177 #if !defined(__LP64__)
178 	uint32_t	 pad;		/* pad for 64bit alignment */
179 #endif
180 	union {
181 		uint64_t	rcv_tstmp;	/* timestamp in ns */
182 		struct {
183 			uint8_t		 l2hlen;	/* layer 2 hdr len */
184 			uint8_t		 l3hlen;	/* layer 3 hdr len */
185 			uint8_t		 l4hlen;	/* layer 4 hdr len */
186 			uint8_t		 l5hlen;	/* layer 5 hdr len */
187 			uint8_t		 inner_l2hlen;
188 			uint8_t		 inner_l3hlen;
189 			uint8_t		 inner_l4hlen;
190 			uint8_t		 inner_l5hlen;
191 		};
192 	};
193 	union {
194 		uint8_t  eight[8];
195 		uint16_t sixteen[4];
196 		uint32_t thirtytwo[2];
197 		uint64_t sixtyfour[1];
198 		uintptr_t unintptr[1];
199 		void	*ptr;
200 	} PH_per;
201 
202 	/* Layer specific non-persistent local storage for reassembly, etc. */
203 	union {
204 		union {
205 			uint8_t  eight[8];
206 			uint16_t sixteen[4];
207 			uint32_t thirtytwo[2];
208 			uint64_t sixtyfour[1];
209 			uintptr_t unintptr[1];
210 			void 	*ptr;
211 		} PH_loc;
212 		/* Upon allocation: total packet memory consumption. */
213 		u_int	memlen;
214 	};
215 };
216 #define	ether_vtag	PH_per.sixteen[0]
217 #define tcp_tun_port	PH_per.sixteen[0] /* outbound */
218 #define	vt_nrecs	PH_per.sixteen[0]	  /* mld and v6-ND */
219 #define	tso_segsz	PH_per.sixteen[1] /* inbound after LRO */
220 #define	lro_nsegs	tso_segsz	  /* inbound after LRO */
221 #define	csum_data	PH_per.thirtytwo[1] /* inbound from hardware up */
222 #define	lro_tcp_d_len	PH_loc.sixteen[0] /* inbound during LRO (no reassembly) */
223 #define	lro_tcp_d_csum	PH_loc.sixteen[1] /* inbound during LRO (no reassembly) */
224 #define	lro_tcp_h_off	PH_loc.sixteen[2] /* inbound during LRO (no reassembly) */
225 #define	lro_etype	PH_loc.sixteen[3] /* inbound during LRO (no reassembly) */
226 /* Note PH_loc is used during IP reassembly (all 8 bytes as a ptr) */
227 
228 /*
229  * TLS records for TLS 1.0-1.2 can have the following header lengths:
230  * - 5 (AES-CBC with implicit IV)
231  * - 21 (AES-CBC with explicit IV)
232  * - 13 (AES-GCM with 8 byte explicit IV)
233  */
234 #define	MBUF_PEXT_HDR_LEN	23
235 
236 /*
237  * TLS records for TLS 1.0-1.2 can have the following maximum trailer
238  * lengths:
239  * - 16 (AES-GCM)
240  * - 36 (AES-CBC with SHA1 and up to 16 bytes of padding)
241  * - 48 (AES-CBC with SHA2-256 and up to 16 bytes of padding)
242  * - 64 (AES-CBC with SHA2-384 and up to 16 bytes of padding)
243  */
244 #define	MBUF_PEXT_TRAIL_LEN	64
245 
246 #if defined(__LP64__)
247 #define MBUF_PEXT_MAX_PGS (40 / sizeof(vm_paddr_t))
248 #else
249 #define MBUF_PEXT_MAX_PGS (64 / sizeof(vm_paddr_t))
250 #endif
251 
252 #define	MBUF_PEXT_MAX_BYTES						\
253     (MBUF_PEXT_MAX_PGS * PAGE_SIZE + MBUF_PEXT_HDR_LEN + MBUF_PEXT_TRAIL_LEN)
254 
255 struct ktls_session;
256 struct socket;
257 
258 /*
259  * Description of external storage mapped into mbuf; valid only if M_EXT is
260  * set.
261  * Size ILP32: 28
262  *	 LP64: 48
263  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
264  * they are correct.
265  */
266 typedef	void m_ext_free_t(struct mbuf *);
267 struct m_ext {
268 	union {
269 		/*
270 		 * If EXT_FLAG_EMBREF is set, then we use refcount in the
271 		 * mbuf, the 'ext_count' member.  Otherwise, we have a
272 		 * shadow copy and we use pointer 'ext_cnt'.  The original
273 		 * mbuf is responsible to carry the pointer to free routine
274 		 * and its arguments.  They aren't copied into shadows in
275 		 * mb_dupcl() to avoid dereferencing next cachelines.
276 		 */
277 		volatile u_int	 ext_count;
278 		volatile u_int	*ext_cnt;
279 	};
280 	uint32_t	 ext_size;	/* size of buffer, for ext_free */
281 	uint32_t	 ext_type:8,	/* type of external storage */
282 			 ext_flags:24;	/* external storage mbuf flags */
283 	union {
284 		struct {
285 			/*
286 			 * Regular M_EXT mbuf:
287 			 * o ext_buf always points to the external buffer.
288 			 * o ext_free (below) and two optional arguments
289 			 *   ext_arg1 and ext_arg2 store the free context for
290 			 *   the external storage.  They are set only in the
291 			 *   refcount carrying mbuf, the one with
292 			 *   EXT_FLAG_EMBREF flag, with exclusion for
293 			 *   EXT_EXTREF type, where the free context is copied
294 			 *   into all mbufs that use same external storage.
295 			 */
296 			char 	*ext_buf;	/* start of buffer */
297 #define	m_ext_copylen	offsetof(struct m_ext, ext_arg2)
298 			void	*ext_arg2;
299 		};
300 		struct {
301 			/*
302 			 * Multi-page M_EXTPG mbuf:
303 			 * o extpg_pa - page vector.
304 			 * o extpg_trail and extpg_hdr - TLS trailer and
305 			 *   header.
306 			 * Uses ext_free and may also use ext_arg1.
307 			 */
308 			vm_paddr_t	extpg_pa[MBUF_PEXT_MAX_PGS];
309 			char		extpg_trail[MBUF_PEXT_TRAIL_LEN];
310 			char		extpg_hdr[MBUF_PEXT_HDR_LEN];
311 			/* Pretend these 3 fields are part of mbuf itself. */
312 #define	m_epg_pa	m_ext.extpg_pa
313 #define	m_epg_trail	m_ext.extpg_trail
314 #define	m_epg_hdr	m_ext.extpg_hdr
315 #define	m_epg_ext_copylen	offsetof(struct m_ext, ext_free)
316 		};
317 	};
318 	/*
319 	 * Free method and optional argument pointer, both
320 	 * used by M_EXT and M_EXTPG.
321 	 */
322 	m_ext_free_t	*ext_free;
323 	void		*ext_arg1;
324 };
325 
326 /*
327  * The core of the mbuf object along with some shortcut defines for practical
328  * purposes.
329  */
330 struct mbuf {
331 	/*
332 	 * Header present at the beginning of every mbuf.
333 	 * Size ILP32: 24
334 	 *      LP64: 32
335 	 * Compile-time assertions in uipc_mbuf.c test these values to ensure
336 	 * that they are correct.
337 	 */
338 	union {	/* next buffer in chain */
339 		struct mbuf		*m_next;
340 		SLIST_ENTRY(mbuf)	m_slist;
341 		STAILQ_ENTRY(mbuf)	m_stailq;
342 	};
343 	union {	/* next chain in queue/record */
344 		struct mbuf		*m_nextpkt;
345 		SLIST_ENTRY(mbuf)	m_slistpkt;
346 		STAILQ_ENTRY(mbuf)	m_stailqpkt;
347 	};
348 	caddr_t		 m_data;	/* location of data */
349 	int32_t		 m_len;		/* amount of data in this mbuf */
350 	uint32_t	 m_type:8,	/* type of data in this mbuf */
351 			 m_flags:24;	/* flags; see below */
352 #if !defined(__LP64__)
353 	uint32_t	 m_pad;		/* pad for 64bit alignment */
354 #endif
355 
356 	/*
357 	 * A set of optional headers (packet header, external storage header)
358 	 * and internal data storage.  Historically, these arrays were sized
359 	 * to MHLEN (space left after a packet header) and MLEN (space left
360 	 * after only a regular mbuf header); they are now variable size in
361 	 * order to support future work on variable-size mbufs.
362 	 */
363 	union {
364 		struct {
365 			union {
366 				/* M_PKTHDR set. */
367 				struct pkthdr	m_pkthdr;
368 
369 				/* M_EXTPG set.
370 				 * Multi-page M_EXTPG mbuf has its meta data
371 				 * split between the below anonymous structure
372 				 * and m_ext.  It carries vector of pages,
373 				 * optional header and trailer char vectors
374 				 * and pointers to socket/TLS data.
375 				 */
376 #define	m_epg_startcopy		m_epg_npgs
377 #define	m_epg_endcopy		m_epg_stailq
378 				struct {
379 					/* Overall count of pages and count of
380 					 * pages with I/O pending. */
381 					uint8_t	m_epg_npgs;
382 					uint8_t	m_epg_nrdy;
383 					/* TLS header and trailer lengths.
384 					 * The data itself resides in m_ext. */
385 					uint8_t	m_epg_hdrlen;
386 					uint8_t	m_epg_trllen;
387 					/* Offset into 1st page and length of
388 					 * data in the last page. */
389 					uint16_t m_epg_1st_off;
390 					uint16_t m_epg_last_len;
391 					uint8_t	m_epg_flags;
392 #define	EPG_FLAG_ANON	0x1	/* Data can be encrypted in place. */
393 #define	EPG_FLAG_2FREE	0x2	/* Scheduled for free. */
394 					uint8_t	m_epg_record_type;
395 					uint8_t	__spare[2];
396 					int	m_epg_enc_cnt;
397 					struct ktls_session *m_epg_tls;
398 					struct socket	*m_epg_so;
399 					uint64_t	m_epg_seqno;
400 					STAILQ_ENTRY(mbuf) m_epg_stailq;
401 				};
402 			};
403 			union {
404 				/* M_EXT or M_EXTPG set. */
405 				struct m_ext	m_ext;
406 				/* M_PKTHDR set, neither M_EXT nor M_EXTPG. */
407 				char		m_pktdat[0];
408 			};
409 		};
410 		char	m_dat[0];			/* !M_PKTHDR, !M_EXT */
411 	};
412 };
413 
414 #ifdef _KERNEL
415 static inline int
416 m_epg_pagelen(const struct mbuf *m, int pidx, int pgoff)
417 {
418 
419 	KASSERT(pgoff == 0 || pidx == 0,
420 	    ("page %d with non-zero offset %d in %p", pidx, pgoff, m));
421 
422 	if (pidx == m->m_epg_npgs - 1) {
423 		return (m->m_epg_last_len);
424 	} else {
425 		return (PAGE_SIZE - pgoff);
426 	}
427 }
428 
429 #ifdef INVARIANTS
430 #define	MCHECK(ex, msg)	KASSERT((ex),				\
431 	    ("Multi page mbuf %p with " #msg " at %s:%d",	\
432 	    m, __FILE__, __LINE__))
433 /*
434  * NB: This expects a non-empty buffer (npgs > 0 and
435  * last_pg_len > 0).
436  */
437 #define	MBUF_EXT_PGS_ASSERT_SANITY(m)	do {				\
438 	MCHECK(m->m_epg_npgs > 0, "no valid pages");		\
439 	MCHECK(m->m_epg_npgs <= nitems(m->m_epg_pa),		\
440 	    "too many pages");						\
441 	MCHECK(m->m_epg_nrdy <= m->m_epg_npgs,			\
442 	    "too many ready pages");					\
443 	MCHECK(m->m_epg_1st_off < PAGE_SIZE,			\
444 		"too large page offset");				\
445 	MCHECK(m->m_epg_last_len > 0, "zero last page length");	\
446 	MCHECK(m->m_epg_last_len <= PAGE_SIZE,			\
447 	    "too large last page length");				\
448 	if (m->m_epg_npgs == 1)					\
449 		MCHECK(m->m_epg_1st_off +			\
450 		    m->m_epg_last_len <=	 PAGE_SIZE,		\
451 		    "single page too large");				\
452 	MCHECK(m->m_epg_hdrlen <= sizeof(m->m_epg_hdr),		\
453 	    "too large header length");					\
454 	MCHECK(m->m_epg_trllen <= sizeof(m->m_epg_trail),	\
455 	    "too large header length");					\
456 } while (0)
457 #else
458 #define	MBUF_EXT_PGS_ASSERT_SANITY(m)	do {} while (0)
459 #endif
460 #endif
461 
462 /*
463  * mbuf flags of global significance and layer crossing.
464  * Those of only protocol/layer specific significance are to be mapped
465  * to M_PROTO[1-11] and cleared at layer handoff boundaries.
466  * NB: Limited to the lower 24 bits.
467  */
468 #define	M_EXT		0x00000001 /* has associated external storage */
469 #define	M_PKTHDR	0x00000002 /* start of record */
470 #define	M_EOR		0x00000004 /* end of record */
471 #define	M_RDONLY	0x00000008 /* associated data is marked read-only */
472 #define	M_BCAST		0x00000010 /* send/received as link-level broadcast */
473 #define	M_MCAST		0x00000020 /* send/received as link-level multicast */
474 #define	M_PROMISC	0x00000040 /* packet was not for us */
475 #define	M_VLANTAG	0x00000080 /* ether_vtag is valid */
476 #define	M_EXTPG		0x00000100 /* has array of unmapped pages and TLS */
477 #define	M_NOFREE	0x00000200 /* do not free mbuf, embedded in cluster */
478 #define	M_TSTMP		0x00000400 /* rcv_tstmp field is valid */
479 #define	M_TSTMP_HPREC	0x00000800 /* rcv_tstmp is high-prec, typically
480 				      hw-stamped on port (useful for IEEE 1588
481 				      and 802.1AS) */
482 #define M_TSTMP_LRO	0x00001000 /* Time LRO pushed in pkt is valid in (PH_loc) */
483 
484 #define	M_PROTO1	0x00002000 /* protocol-specific */
485 #define	M_PROTO2	0x00004000 /* protocol-specific */
486 #define	M_PROTO3	0x00008000 /* protocol-specific */
487 #define	M_PROTO4	0x00010000 /* protocol-specific */
488 #define	M_PROTO5	0x00020000 /* protocol-specific */
489 #define	M_PROTO6	0x00040000 /* protocol-specific */
490 #define	M_PROTO7	0x00080000 /* protocol-specific */
491 #define	M_PROTO8	0x00100000 /* protocol-specific */
492 #define	M_PROTO9	0x00200000 /* protocol-specific */
493 #define	M_PROTO10	0x00400000 /* protocol-specific */
494 #define	M_PROTO11	0x00800000 /* protocol-specific */
495 
496 /*
497  * Flags to purge when crossing layers.
498  */
499 #define	M_PROTOFLAGS \
500     (M_PROTO1|M_PROTO2|M_PROTO3|M_PROTO4|M_PROTO5|M_PROTO6|M_PROTO7|M_PROTO8|\
501      M_PROTO9|M_PROTO10|M_PROTO11)
502 
503 /*
504  * Flags preserved when copying m_pkthdr.
505  */
506 #define M_COPYFLAGS \
507     (M_PKTHDR|M_EOR|M_RDONLY|M_BCAST|M_MCAST|M_PROMISC|M_VLANTAG|M_TSTMP| \
508      M_TSTMP_HPREC|M_TSTMP_LRO|M_PROTOFLAGS)
509 
510 /*
511  * Flags preserved during demote.
512  */
513 #define	M_DEMOTEFLAGS \
514     (M_EXT | M_RDONLY | M_NOFREE | M_EXTPG)
515 
516 /*
517  * Mbuf flag description for use with printf(9) %b identifier.
518  */
519 #define	M_FLAG_BITS \
520     "\20\1M_EXT\2M_PKTHDR\3M_EOR\4M_RDONLY\5M_BCAST\6M_MCAST" \
521     "\7M_PROMISC\10M_VLANTAG\11M_EXTPG\12M_NOFREE\13M_TSTMP\14M_TSTMP_HPREC\15M_TSTMP_LRO"
522 #define	M_FLAG_PROTOBITS \
523     "\16M_PROTO1\17M_PROTO2\20M_PROTO3\21M_PROTO4" \
524     "\22M_PROTO5\23M_PROTO6\24M_PROTO7\25M_PROTO8\26M_PROTO9" \
525     "\27M_PROTO10\28M_PROTO11"
526 #define	M_FLAG_PRINTF (M_FLAG_BITS M_FLAG_PROTOBITS)
527 
528 /*
529  * Network interface cards are able to hash protocol fields (such as IPv4
530  * addresses and TCP port numbers) classify packets into flows.  These flows
531  * can then be used to maintain ordering while delivering packets to the OS
532  * via parallel input queues, as well as to provide a stateless affinity
533  * model.  NIC drivers can pass up the hash via m->m_pkthdr.flowid, and set
534  * m_flag fields to indicate how the hash should be interpreted by the
535  * network stack.
536  *
537  * Most NICs support RSS, which provides ordering and explicit affinity, and
538  * use the hash m_flag bits to indicate what header fields were covered by
539  * the hash.  M_HASHTYPE_OPAQUE and M_HASHTYPE_OPAQUE_HASH can be set by non-
540  * RSS cards or configurations that provide an opaque flow identifier, allowing
541  * for ordering and distribution without explicit affinity.  Additionally,
542  * M_HASHTYPE_OPAQUE_HASH indicates that the flow identifier has hash
543  * properties.
544  *
545  * The meaning of the IPV6_EX suffix:
546  * "o  Home address from the home address option in the IPv6 destination
547  *     options header.  If the extension header is not present, use the Source
548  *     IPv6 Address.
549  *  o  IPv6 address that is contained in the Routing-Header-Type-2 from the
550  *     associated extension header.  If the extension header is not present,
551  *     use the Destination IPv6 Address."
552  * Quoted from:
553  * https://docs.microsoft.com/en-us/windows-hardware/drivers/network/rss-hashing-types#ndishashipv6ex
554  */
555 #define	M_HASHTYPE_HASHPROP		0x80	/* has hash properties */
556 #define	M_HASHTYPE_INNER		0x40	/* calculated from inner headers */
557 #define	M_HASHTYPE_HASH(t)		(M_HASHTYPE_HASHPROP | (t))
558 /* Microsoft RSS standard hash types */
559 #define	M_HASHTYPE_NONE			0
560 #define	M_HASHTYPE_RSS_IPV4		M_HASHTYPE_HASH(1) /* IPv4 2-tuple */
561 #define	M_HASHTYPE_RSS_TCP_IPV4		M_HASHTYPE_HASH(2) /* TCPv4 4-tuple */
562 #define	M_HASHTYPE_RSS_IPV6		M_HASHTYPE_HASH(3) /* IPv6 2-tuple */
563 #define	M_HASHTYPE_RSS_TCP_IPV6		M_HASHTYPE_HASH(4) /* TCPv6 4-tuple */
564 #define	M_HASHTYPE_RSS_IPV6_EX		M_HASHTYPE_HASH(5) /* IPv6 2-tuple +
565 							    * ext hdrs */
566 #define	M_HASHTYPE_RSS_TCP_IPV6_EX	M_HASHTYPE_HASH(6) /* TCPv6 4-tuple +
567 							    * ext hdrs */
568 #define	M_HASHTYPE_RSS_UDP_IPV4		M_HASHTYPE_HASH(7) /* IPv4 UDP 4-tuple*/
569 #define	M_HASHTYPE_RSS_UDP_IPV6		M_HASHTYPE_HASH(9) /* IPv6 UDP 4-tuple*/
570 #define	M_HASHTYPE_RSS_UDP_IPV6_EX	M_HASHTYPE_HASH(10)/* IPv6 UDP 4-tuple +
571 							    * ext hdrs */
572 
573 #define	M_HASHTYPE_OPAQUE		0x3f	/* ordering, not affinity */
574 #define	M_HASHTYPE_OPAQUE_HASH		M_HASHTYPE_HASH(M_HASHTYPE_OPAQUE)
575 						/* ordering+hash, not affinity*/
576 
577 #define	M_HASHTYPE_CLEAR(m)	((m)->m_pkthdr.rsstype = 0)
578 #define	M_HASHTYPE_GET(m)	((m)->m_pkthdr.rsstype & ~M_HASHTYPE_INNER)
579 #define	M_HASHTYPE_SET(m, v)	((m)->m_pkthdr.rsstype = (v))
580 #define	M_HASHTYPE_TEST(m, v)	(M_HASHTYPE_GET(m) == (v))
581 #define	M_HASHTYPE_ISHASH(m)	\
582     (((m)->m_pkthdr.rsstype & M_HASHTYPE_HASHPROP) != 0)
583 #define	M_HASHTYPE_SETINNER(m)	do {			\
584 	(m)->m_pkthdr.rsstype |= M_HASHTYPE_INNER;	\
585     } while (0)
586 
587 /*
588  * External mbuf storage buffer types.
589  */
590 #define	EXT_CLUSTER	1	/* mbuf cluster */
591 #define	EXT_SFBUF	2	/* sendfile(2)'s sf_buf */
592 #define	EXT_JUMBOP	3	/* jumbo cluster page sized */
593 #define	EXT_JUMBO9	4	/* jumbo cluster 9216 bytes */
594 #define	EXT_JUMBO16	5	/* jumbo cluster 16184 bytes */
595 #define	EXT_PACKET	6	/* mbuf+cluster from packet zone */
596 #define	EXT_MBUF	7	/* external mbuf reference */
597 #define	EXT_RXRING	8	/* data in NIC receive ring */
598 
599 #define	EXT_VENDOR1	224	/* for vendor-internal use */
600 #define	EXT_VENDOR2	225	/* for vendor-internal use */
601 #define	EXT_VENDOR3	226	/* for vendor-internal use */
602 #define	EXT_VENDOR4	227	/* for vendor-internal use */
603 
604 #define	EXT_EXP1	244	/* for experimental use */
605 #define	EXT_EXP2	245	/* for experimental use */
606 #define	EXT_EXP3	246	/* for experimental use */
607 #define	EXT_EXP4	247	/* for experimental use */
608 
609 #define	EXT_NET_DRV	252	/* custom ext_buf provided by net driver(s) */
610 #define	EXT_MOD_TYPE	253	/* custom module's ext_buf type */
611 #define	EXT_DISPOSABLE	254	/* can throw this buffer away w/page flipping */
612 #define	EXT_EXTREF	255	/* has externally maintained ext_cnt ptr */
613 
614 /*
615  * Flags for external mbuf buffer types.
616  * NB: limited to the lower 24 bits.
617  */
618 #define	EXT_FLAG_EMBREF		0x000001	/* embedded ext_count */
619 #define	EXT_FLAG_EXTREF		0x000002	/* external ext_cnt, notyet */
620 
621 #define	EXT_FLAG_NOFREE		0x000010	/* don't free mbuf to pool, notyet */
622 
623 #define	EXT_FLAG_VENDOR1	0x010000	/* These flags are vendor */
624 #define	EXT_FLAG_VENDOR2	0x020000	/* or submodule specific, */
625 #define	EXT_FLAG_VENDOR3	0x040000	/* not used by mbuf code. */
626 #define	EXT_FLAG_VENDOR4	0x080000	/* Set/read by submodule. */
627 
628 #define	EXT_FLAG_EXP1		0x100000	/* for experimental use */
629 #define	EXT_FLAG_EXP2		0x200000	/* for experimental use */
630 #define	EXT_FLAG_EXP3		0x400000	/* for experimental use */
631 #define	EXT_FLAG_EXP4		0x800000	/* for experimental use */
632 
633 /*
634  * EXT flag description for use with printf(9) %b identifier.
635  */
636 #define	EXT_FLAG_BITS \
637     "\20\1EXT_FLAG_EMBREF\2EXT_FLAG_EXTREF\5EXT_FLAG_NOFREE" \
638     "\21EXT_FLAG_VENDOR1\22EXT_FLAG_VENDOR2\23EXT_FLAG_VENDOR3" \
639     "\24EXT_FLAG_VENDOR4\25EXT_FLAG_EXP1\26EXT_FLAG_EXP2\27EXT_FLAG_EXP3" \
640     "\30EXT_FLAG_EXP4"
641 
642 /*
643  * Flags indicating checksum, segmentation and other offload work to be
644  * done, or already done, by hardware or lower layers.  It is split into
645  * separate inbound and outbound flags.
646  *
647  * Outbound flags that are set by upper protocol layers requesting lower
648  * layers, or ideally the hardware, to perform these offloading tasks.
649  * For outbound packets this field and its flags can be directly tested
650  * against ifnet if_hwassist.  Note that the outbound and the inbound flags do
651  * not collide right now but they could be allowed to (as long as the flags are
652  * scrubbed appropriately when the direction of an mbuf changes).  CSUM_BITS
653  * would also have to split into CSUM_BITS_TX and CSUM_BITS_RX.
654  *
655  * CSUM_INNER_<x> is the same as CSUM_<x> but it applies to the inner frame.
656  * The CSUM_ENCAP_<x> bits identify the outer encapsulation.
657  */
658 #define	CSUM_IP			0x00000001	/* IP header checksum offload */
659 #define	CSUM_IP_UDP		0x00000002	/* UDP checksum offload */
660 #define	CSUM_IP_TCP		0x00000004	/* TCP checksum offload */
661 #define	CSUM_IP_SCTP		0x00000008	/* SCTP checksum offload */
662 #define	CSUM_IP_TSO		0x00000010	/* TCP segmentation offload */
663 #define	CSUM_IP_ISCSI		0x00000020	/* iSCSI checksum offload */
664 
665 #define	CSUM_INNER_IP6_UDP	0x00000040
666 #define	CSUM_INNER_IP6_TCP	0x00000080
667 #define	CSUM_INNER_IP6_TSO	0x00000100
668 #define	CSUM_IP6_UDP		0x00000200	/* UDP checksum offload */
669 #define	CSUM_IP6_TCP		0x00000400	/* TCP checksum offload */
670 #define	CSUM_IP6_SCTP		0x00000800	/* SCTP checksum offload */
671 #define	CSUM_IP6_TSO		0x00001000	/* TCP segmentation offload */
672 #define	CSUM_IP6_ISCSI		0x00002000	/* iSCSI checksum offload */
673 
674 #define	CSUM_INNER_IP		0x00004000
675 #define	CSUM_INNER_IP_UDP	0x00008000
676 #define	CSUM_INNER_IP_TCP	0x00010000
677 #define	CSUM_INNER_IP_TSO	0x00020000
678 
679 #define	CSUM_ENCAP_VXLAN	0x00040000	/* VXLAN outer encapsulation */
680 #define	CSUM_ENCAP_RSVD1	0x00080000
681 
682 /* Inbound checksum support where the checksum was verified by hardware. */
683 #define	CSUM_INNER_L3_CALC	0x00100000
684 #define	CSUM_INNER_L3_VALID	0x00200000
685 #define	CSUM_INNER_L4_CALC	0x00400000
686 #define	CSUM_INNER_L4_VALID	0x00800000
687 #define	CSUM_L3_CALC		0x01000000	/* calculated layer 3 csum */
688 #define	CSUM_L3_VALID		0x02000000	/* checksum is correct */
689 #define	CSUM_L4_CALC		0x04000000	/* calculated layer 4 csum */
690 #define	CSUM_L4_VALID		0x08000000	/* checksum is correct */
691 #define	CSUM_L5_CALC		0x10000000	/* calculated layer 5 csum */
692 #define	CSUM_L5_VALID		0x20000000	/* checksum is correct */
693 #define	CSUM_COALESCED		0x40000000	/* contains merged segments */
694 
695 #define	CSUM_SND_TAG		0x80000000	/* Packet header has send tag */
696 
697 #define CSUM_FLAGS_TX (CSUM_IP | CSUM_IP_UDP | CSUM_IP_TCP | CSUM_IP_SCTP | \
698     CSUM_IP_TSO | CSUM_IP_ISCSI | CSUM_INNER_IP6_UDP | CSUM_INNER_IP6_TCP | \
699     CSUM_INNER_IP6_TSO | CSUM_IP6_UDP | CSUM_IP6_TCP | CSUM_IP6_SCTP | \
700     CSUM_IP6_TSO | CSUM_IP6_ISCSI | CSUM_INNER_IP | CSUM_INNER_IP_UDP | \
701     CSUM_INNER_IP_TCP | CSUM_INNER_IP_TSO | CSUM_ENCAP_VXLAN | \
702     CSUM_ENCAP_RSVD1 | CSUM_SND_TAG)
703 
704 #define CSUM_FLAGS_RX (CSUM_INNER_L3_CALC | CSUM_INNER_L3_VALID | \
705     CSUM_INNER_L4_CALC | CSUM_INNER_L4_VALID | CSUM_L3_CALC | CSUM_L3_VALID | \
706     CSUM_L4_CALC | CSUM_L4_VALID | CSUM_L5_CALC | CSUM_L5_VALID | \
707     CSUM_COALESCED)
708 
709 /*
710  * CSUM flag description for use with printf(9) %b identifier.
711  */
712 #define	CSUM_BITS \
713     "\20\1CSUM_IP\2CSUM_IP_UDP\3CSUM_IP_TCP\4CSUM_IP_SCTP\5CSUM_IP_TSO" \
714     "\6CSUM_IP_ISCSI\7CSUM_INNER_IP6_UDP\10CSUM_INNER_IP6_TCP" \
715     "\11CSUM_INNER_IP6_TSO\12CSUM_IP6_UDP\13CSUM_IP6_TCP\14CSUM_IP6_SCTP" \
716     "\15CSUM_IP6_TSO\16CSUM_IP6_ISCSI\17CSUM_INNER_IP\20CSUM_INNER_IP_UDP" \
717     "\21CSUM_INNER_IP_TCP\22CSUM_INNER_IP_TSO\23CSUM_ENCAP_VXLAN" \
718     "\24CSUM_ENCAP_RSVD1\25CSUM_INNER_L3_CALC\26CSUM_INNER_L3_VALID" \
719     "\27CSUM_INNER_L4_CALC\30CSUM_INNER_L4_VALID\31CSUM_L3_CALC" \
720     "\32CSUM_L3_VALID\33CSUM_L4_CALC\34CSUM_L4_VALID\35CSUM_L5_CALC" \
721     "\36CSUM_L5_VALID\37CSUM_COALESCED\40CSUM_SND_TAG"
722 
723 /* CSUM flags compatibility mappings. */
724 #define	CSUM_IP_CHECKED		CSUM_L3_CALC
725 #define	CSUM_IP_VALID		CSUM_L3_VALID
726 #define	CSUM_DATA_VALID		CSUM_L4_VALID
727 #define	CSUM_PSEUDO_HDR		CSUM_L4_CALC
728 #define	CSUM_SCTP_VALID		CSUM_L4_VALID
729 #define	CSUM_DELAY_DATA		(CSUM_TCP|CSUM_UDP)
730 #define	CSUM_DELAY_IP		CSUM_IP		/* Only v4, no v6 IP hdr csum */
731 #define	CSUM_DELAY_DATA_IPV6	(CSUM_TCP_IPV6|CSUM_UDP_IPV6)
732 #define	CSUM_DATA_VALID_IPV6	CSUM_DATA_VALID
733 #define	CSUM_TCP		CSUM_IP_TCP
734 #define	CSUM_UDP		CSUM_IP_UDP
735 #define	CSUM_SCTP		CSUM_IP_SCTP
736 #define	CSUM_TSO		(CSUM_IP_TSO|CSUM_IP6_TSO)
737 #define	CSUM_INNER_TSO		(CSUM_INNER_IP_TSO|CSUM_INNER_IP6_TSO)
738 #define	CSUM_UDP_IPV6		CSUM_IP6_UDP
739 #define	CSUM_TCP_IPV6		CSUM_IP6_TCP
740 #define	CSUM_SCTP_IPV6		CSUM_IP6_SCTP
741 #define	CSUM_TLS_MASK		(CSUM_L5_CALC|CSUM_L5_VALID)
742 #define	CSUM_TLS_DECRYPTED	CSUM_L5_CALC
743 
744 /*
745  * mbuf types describing the content of the mbuf (including external storage).
746  */
747 #define	MT_NOTMBUF	0	/* USED INTERNALLY ONLY! Object is not mbuf */
748 #define	MT_DATA		1	/* dynamic (data) allocation */
749 #define	MT_HEADER	MT_DATA	/* packet header, use M_PKTHDR instead */
750 
751 #define	MT_VENDOR1	4	/* for vendor-internal use */
752 #define	MT_VENDOR2	5	/* for vendor-internal use */
753 #define	MT_VENDOR3	6	/* for vendor-internal use */
754 #define	MT_VENDOR4	7	/* for vendor-internal use */
755 
756 #define	MT_SONAME	8	/* socket name */
757 
758 #define	MT_EXP1		9	/* for experimental use */
759 #define	MT_EXP2		10	/* for experimental use */
760 #define	MT_EXP3		11	/* for experimental use */
761 #define	MT_EXP4		12	/* for experimental use */
762 
763 #define	MT_CONTROL	14	/* extra-data protocol message */
764 #define	MT_EXTCONTROL	15	/* control message with externalized contents */
765 #define	MT_OOBDATA	16	/* expedited data  */
766 
767 #define	MT_NOINIT	255	/* Not a type but a flag to allocate
768 				   a non-initialized mbuf */
769 
770 /*
771  * String names of mbuf-related UMA(9) and malloc(9) types.  Exposed to
772  * !_KERNEL so that monitoring tools can look up the zones with
773  * libmemstat(3).
774  */
775 #define	MBUF_MEM_NAME		"mbuf"
776 #define	MBUF_CLUSTER_MEM_NAME	"mbuf_cluster"
777 #define	MBUF_PACKET_MEM_NAME	"mbuf_packet"
778 #define	MBUF_JUMBOP_MEM_NAME	"mbuf_jumbo_page"
779 #define	MBUF_JUMBO9_MEM_NAME	"mbuf_jumbo_9k"
780 #define	MBUF_JUMBO16_MEM_NAME	"mbuf_jumbo_16k"
781 #define	MBUF_TAG_MEM_NAME	"mbuf_tag"
782 #define	MBUF_EXTREFCNT_MEM_NAME	"mbuf_ext_refcnt"
783 #define	MBUF_EXTPGS_MEM_NAME	"mbuf_extpgs"
784 
785 #ifdef _KERNEL
786 union if_snd_tag_alloc_params;
787 
788 #define	MBUF_CHECKSLEEP(how) do {					\
789 	if (how == M_WAITOK)						\
790 		WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,		\
791 		    "Sleeping in \"%s\"", __func__);			\
792 } while (0)
793 
794 /*
795  * Network buffer allocation API
796  *
797  * The rest of it is defined in kern/kern_mbuf.c
798  */
799 extern uma_zone_t	zone_mbuf;
800 extern uma_zone_t	zone_clust;
801 extern uma_zone_t	zone_pack;
802 extern uma_zone_t	zone_jumbop;
803 extern uma_zone_t	zone_jumbo9;
804 extern uma_zone_t	zone_jumbo16;
805 extern uma_zone_t	zone_extpgs;
806 
807 void		 mb_dupcl(struct mbuf *, struct mbuf *);
808 void		 mb_free_ext(struct mbuf *);
809 void		 mb_free_extpg(struct mbuf *);
810 void		 mb_free_mext_pgs(struct mbuf *);
811 struct mbuf	*mb_alloc_ext_pgs(int, m_ext_free_t);
812 struct mbuf	*mb_alloc_ext_plus_pages(int, int);
813 struct mbuf	*mb_mapped_to_unmapped(struct mbuf *, int, int, int,
814 		    struct mbuf **);
815 int		 mb_unmapped_compress(struct mbuf *m);
816 struct mbuf 	*mb_unmapped_to_ext(struct mbuf *m);
817 void		 mb_free_notready(struct mbuf *m, int count);
818 void		 m_adj(struct mbuf *, int);
819 void		 m_adj_decap(struct mbuf *, int);
820 int		 m_apply(struct mbuf *, int, int,
821 		    int (*)(void *, void *, u_int), void *);
822 int		 m_append(struct mbuf *, int, c_caddr_t);
823 void		 m_cat(struct mbuf *, struct mbuf *);
824 void		 m_catpkt(struct mbuf *, struct mbuf *);
825 int		 m_clget(struct mbuf *m, int how);
826 void 		*m_cljget(struct mbuf *m, int how, int size);
827 struct mbuf	*m_collapse(struct mbuf *, int, int);
828 void		 m_copyback(struct mbuf *, int, int, c_caddr_t);
829 void		 m_copydata(const struct mbuf *, int, int, caddr_t);
830 struct mbuf	*m_copym(struct mbuf *, int, int, int);
831 struct mbuf	*m_copypacket(struct mbuf *, int);
832 void		 m_copy_pkthdr(struct mbuf *, struct mbuf *);
833 struct mbuf	*m_copyup(struct mbuf *, int, int);
834 struct mbuf	*m_defrag(struct mbuf *, int);
835 void		 m_demote_pkthdr(struct mbuf *);
836 void		 m_demote(struct mbuf *, int, int);
837 struct mbuf	*m_devget(char *, int, int, struct ifnet *,
838 		    void (*)(char *, caddr_t, u_int));
839 void		 m_dispose_extcontrolm(struct mbuf *m);
840 struct mbuf	*m_dup(const struct mbuf *, int);
841 int		 m_dup_pkthdr(struct mbuf *, const struct mbuf *, int);
842 void		 m_extadd(struct mbuf *, char *, u_int, m_ext_free_t,
843 		    void *, void *, int, int);
844 u_int		 m_fixhdr(struct mbuf *);
845 struct mbuf	*m_fragment(struct mbuf *, int, int);
846 void		 m_freem(struct mbuf *);
847 void		 m_free_raw(struct mbuf *);
848 struct mbuf	*m_get2(int, int, short, int);
849 struct mbuf	*m_get3(int, int, short, int);
850 struct mbuf	*m_getjcl(int, short, int, int);
851 struct mbuf	*m_getm2(struct mbuf *, int, int, short, int);
852 struct mbuf	*m_getptr(struct mbuf *, int, int *);
853 u_int		 m_length(struct mbuf *, struct mbuf **);
854 int		 m_mbuftouio(struct uio *, const struct mbuf *, int);
855 void		 m_move_pkthdr(struct mbuf *, struct mbuf *);
856 int		 m_pkthdr_init(struct mbuf *, int);
857 struct mbuf	*m_prepend(struct mbuf *, int, int);
858 void		 m_print(const struct mbuf *, int);
859 struct mbuf	*m_pulldown(struct mbuf *, int, int, int *);
860 struct mbuf	*m_pullup(struct mbuf *, int);
861 int		 m_sanity(struct mbuf *, int);
862 struct mbuf	*m_split(struct mbuf *, int, int);
863 struct mbuf	*m_uiotombuf(struct uio *, int, int, int, int);
864 int		 m_unmapped_uiomove(const struct mbuf *, int, struct uio *,
865 		    int);
866 struct mbuf	*m_unshare(struct mbuf *, int);
867 int		 m_snd_tag_alloc(struct ifnet *,
868 		    union if_snd_tag_alloc_params *, struct m_snd_tag **);
869 void		 m_snd_tag_init(struct m_snd_tag *, struct ifnet *,
870 		    const struct if_snd_tag_sw *);
871 void		 m_snd_tag_destroy(struct m_snd_tag *);
872 void		 m_rcvif_serialize(struct mbuf *);
873 struct ifnet	*m_rcvif_restore(struct mbuf *);
874 
875 static __inline int
876 m_gettype(int size)
877 {
878 	int type;
879 
880 	switch (size) {
881 	case MSIZE:
882 		type = EXT_MBUF;
883 		break;
884 	case MCLBYTES:
885 		type = EXT_CLUSTER;
886 		break;
887 	case MJUMPAGESIZE:
888 		type = EXT_JUMBOP;
889 		break;
890 	case MJUM9BYTES:
891 		type = EXT_JUMBO9;
892 		break;
893 	case MJUM16BYTES:
894 		type = EXT_JUMBO16;
895 		break;
896 	default:
897 		panic("%s: invalid cluster size %d", __func__, size);
898 	}
899 
900 	return (type);
901 }
902 
903 /*
904  * Associated an external reference counted buffer with an mbuf.
905  */
906 static __inline void
907 m_extaddref(struct mbuf *m, char *buf, u_int size, u_int *ref_cnt,
908     m_ext_free_t freef, void *arg1, void *arg2)
909 {
910 
911 	KASSERT(ref_cnt != NULL, ("%s: ref_cnt not provided", __func__));
912 
913 	atomic_add_int(ref_cnt, 1);
914 	m->m_flags |= M_EXT;
915 	m->m_ext.ext_buf = buf;
916 	m->m_ext.ext_cnt = ref_cnt;
917 	m->m_data = m->m_ext.ext_buf;
918 	m->m_ext.ext_size = size;
919 	m->m_ext.ext_free = freef;
920 	m->m_ext.ext_arg1 = arg1;
921 	m->m_ext.ext_arg2 = arg2;
922 	m->m_ext.ext_type = EXT_EXTREF;
923 	m->m_ext.ext_flags = 0;
924 }
925 
926 static __inline uma_zone_t
927 m_getzone(int size)
928 {
929 	uma_zone_t zone;
930 
931 	switch (size) {
932 	case MCLBYTES:
933 		zone = zone_clust;
934 		break;
935 	case MJUMPAGESIZE:
936 		zone = zone_jumbop;
937 		break;
938 	case MJUM9BYTES:
939 		zone = zone_jumbo9;
940 		break;
941 	case MJUM16BYTES:
942 		zone = zone_jumbo16;
943 		break;
944 	default:
945 		panic("%s: invalid cluster size %d", __func__, size);
946 	}
947 
948 	return (zone);
949 }
950 
951 /*
952  * Initialize an mbuf with linear storage.
953  *
954  * Inline because the consumer text overhead will be roughly the same to
955  * initialize or call a function with this many parameters and M_PKTHDR
956  * should go away with constant propagation for !MGETHDR.
957  */
958 static __inline int
959 m_init(struct mbuf *m, int how, short type, int flags)
960 {
961 	int error;
962 
963 	m->m_next = NULL;
964 	m->m_nextpkt = NULL;
965 	m->m_data = m->m_dat;
966 	m->m_len = 0;
967 	m->m_flags = flags;
968 	m->m_type = type;
969 	if (flags & M_PKTHDR)
970 		error = m_pkthdr_init(m, how);
971 	else
972 		error = 0;
973 
974 	MBUF_PROBE5(m__init, m, how, type, flags, error);
975 	return (error);
976 }
977 
978 static __inline struct mbuf *
979 m_get_raw(int how, short type)
980 {
981 	struct mbuf *m;
982 	struct mb_args args;
983 
984 	args.flags = 0;
985 	args.type = type | MT_NOINIT;
986 	m = uma_zalloc_arg(zone_mbuf, &args, how);
987 	MBUF_PROBE3(m__get_raw, how, type, m);
988 	return (m);
989 }
990 
991 static __inline struct mbuf *
992 m_get(int how, short type)
993 {
994 	struct mbuf *m;
995 	struct mb_args args;
996 
997 	args.flags = 0;
998 	args.type = type;
999 	m = uma_zalloc_arg(zone_mbuf, &args, how);
1000 	MBUF_PROBE3(m__get, how, type, m);
1001 	return (m);
1002 }
1003 
1004 static __inline struct mbuf *
1005 m_gethdr_raw(int how, short type)
1006 {
1007 	struct mbuf *m;
1008 	struct mb_args args;
1009 
1010 	args.flags = M_PKTHDR;
1011 	args.type = type | MT_NOINIT;
1012 	m = uma_zalloc_arg(zone_mbuf, &args, how);
1013 	MBUF_PROBE3(m__gethdr_raw, how, type, m);
1014 	return (m);
1015 }
1016 
1017 static __inline struct mbuf *
1018 m_gethdr(int how, short type)
1019 {
1020 	struct mbuf *m;
1021 	struct mb_args args;
1022 
1023 	args.flags = M_PKTHDR;
1024 	args.type = type;
1025 	m = uma_zalloc_arg(zone_mbuf, &args, how);
1026 	MBUF_PROBE3(m__gethdr, how, type, m);
1027 	return (m);
1028 }
1029 
1030 static __inline struct mbuf *
1031 m_getcl(int how, short type, int flags)
1032 {
1033 	struct mbuf *m;
1034 	struct mb_args args;
1035 
1036 	args.flags = flags;
1037 	args.type = type;
1038 	m = uma_zalloc_arg(zone_pack, &args, how);
1039 	MBUF_PROBE4(m__getcl, how, type, flags, m);
1040 	return (m);
1041 }
1042 
1043 /*
1044  * XXX: m_cljset() is a dangerous API.  One must attach only a new,
1045  * unreferenced cluster to an mbuf(9).  It is not possible to assert
1046  * that, so care can be taken only by users of the API.
1047  */
1048 static __inline void
1049 m_cljset(struct mbuf *m, void *cl, int type)
1050 {
1051 	int size;
1052 
1053 	switch (type) {
1054 	case EXT_CLUSTER:
1055 		size = MCLBYTES;
1056 		break;
1057 	case EXT_JUMBOP:
1058 		size = MJUMPAGESIZE;
1059 		break;
1060 	case EXT_JUMBO9:
1061 		size = MJUM9BYTES;
1062 		break;
1063 	case EXT_JUMBO16:
1064 		size = MJUM16BYTES;
1065 		break;
1066 	default:
1067 		panic("%s: unknown cluster type %d", __func__, type);
1068 		break;
1069 	}
1070 
1071 	m->m_data = m->m_ext.ext_buf = cl;
1072 	m->m_ext.ext_free = m->m_ext.ext_arg1 = m->m_ext.ext_arg2 = NULL;
1073 	m->m_ext.ext_size = size;
1074 	m->m_ext.ext_type = type;
1075 	m->m_ext.ext_flags = EXT_FLAG_EMBREF;
1076 	m->m_ext.ext_count = 1;
1077 	m->m_flags |= M_EXT;
1078 	MBUF_PROBE3(m__cljset, m, cl, type);
1079 }
1080 
1081 static __inline void
1082 m_chtype(struct mbuf *m, short new_type)
1083 {
1084 
1085 	m->m_type = new_type;
1086 }
1087 
1088 static __inline void
1089 m_clrprotoflags(struct mbuf *m)
1090 {
1091 
1092 	while (m) {
1093 		m->m_flags &= ~M_PROTOFLAGS;
1094 		m = m->m_next;
1095 	}
1096 }
1097 
1098 static __inline struct mbuf *
1099 m_last(struct mbuf *m)
1100 {
1101 
1102 	while (m->m_next)
1103 		m = m->m_next;
1104 	return (m);
1105 }
1106 
1107 static inline u_int
1108 m_extrefcnt(struct mbuf *m)
1109 {
1110 
1111 	KASSERT(m->m_flags & M_EXT, ("%s: M_EXT missing", __func__));
1112 
1113 	return ((m->m_ext.ext_flags & EXT_FLAG_EMBREF) ? m->m_ext.ext_count :
1114 	    *m->m_ext.ext_cnt);
1115 }
1116 
1117 /*
1118  * mbuf, cluster, and external object allocation macros (for compatibility
1119  * purposes).
1120  */
1121 #define	M_MOVE_PKTHDR(to, from)	m_move_pkthdr((to), (from))
1122 #define	MGET(m, how, type)	((m) = m_get((how), (type)))
1123 #define	MGETHDR(m, how, type)	((m) = m_gethdr((how), (type)))
1124 #define	MCLGET(m, how)		m_clget((m), (how))
1125 #define	MEXTADD(m, buf, size, free, arg1, arg2, flags, type)		\
1126     m_extadd((m), (char *)(buf), (size), (free), (arg1), (arg2),	\
1127     (flags), (type))
1128 #define	m_getm(m, len, how, type)					\
1129     m_getm2((m), (len), (how), (type), M_PKTHDR)
1130 
1131 /*
1132  * Evaluate TRUE if it's safe to write to the mbuf m's data region (this can
1133  * be both the local data payload, or an external buffer area, depending on
1134  * whether M_EXT is set).
1135  */
1136 #define	M_WRITABLE(m)	(((m)->m_flags & (M_RDONLY | M_EXTPG)) == 0 &&	\
1137 			 (!(((m)->m_flags & M_EXT)) ||			\
1138 			 (m_extrefcnt(m) == 1)))
1139 
1140 /* Check if the supplied mbuf has a packet header, or else panic. */
1141 #define	M_ASSERTPKTHDR(m)						\
1142 	KASSERT((m) != NULL && (m)->m_flags & M_PKTHDR,			\
1143 	    ("%s: no mbuf packet header!", __func__))
1144 
1145 /* Check if the supplied mbuf has no send tag, or else panic. */
1146 #define	M_ASSERT_NO_SND_TAG(m)						\
1147 	KASSERT((m) != NULL && (m)->m_flags & M_PKTHDR &&		\
1148 	       ((m)->m_pkthdr.csum_flags & CSUM_SND_TAG) == 0,		\
1149 	    ("%s: receive mbuf has send tag!", __func__))
1150 
1151 /* Check if mbuf is multipage. */
1152 #define M_ASSERTEXTPG(m)						\
1153 	KASSERT(((m)->m_flags & (M_EXTPG|M_PKTHDR)) == M_EXTPG,		\
1154 	    ("%s: m %p is not multipage!", __func__, m))
1155 
1156 /*
1157  * Ensure that the supplied mbuf is a valid, non-free mbuf.
1158  *
1159  * XXX: Broken at the moment.  Need some UMA magic to make it work again.
1160  */
1161 #define	M_ASSERTVALID(m)						\
1162 	KASSERT((((struct mbuf *)m)->m_flags & 0) == 0,			\
1163 	    ("%s: attempted use of a free mbuf!", __func__))
1164 
1165 /* Check whether any mbuf in the chain is unmapped. */
1166 #ifdef INVARIANTS
1167 #define	M_ASSERTMAPPED(m) do {						\
1168 	for (struct mbuf *__m = (m); __m != NULL; __m = __m->m_next)	\
1169 		KASSERT((__m->m_flags & M_EXTPG) == 0,			\
1170 		    ("%s: chain %p contains an unmapped mbuf", __func__, (m)));\
1171 } while (0)
1172 #else
1173 #define	M_ASSERTMAPPED(m) do {} while (0)
1174 #endif
1175 
1176 /*
1177  * Return the address of the start of the buffer associated with an mbuf,
1178  * handling external storage, packet-header mbufs, and regular data mbufs.
1179  */
1180 #define	M_START(m)							\
1181 	(((m)->m_flags & M_EXTPG) ? NULL :				\
1182 	 ((m)->m_flags & M_EXT) ? (m)->m_ext.ext_buf :			\
1183 	 ((m)->m_flags & M_PKTHDR) ? &(m)->m_pktdat[0] :		\
1184 	 &(m)->m_dat[0])
1185 
1186 /*
1187  * Return the size of the buffer associated with an mbuf, handling external
1188  * storage, packet-header mbufs, and regular data mbufs.
1189  */
1190 #define	M_SIZE(m)							\
1191 	(((m)->m_flags & M_EXT) ? (m)->m_ext.ext_size :			\
1192 	 ((m)->m_flags & M_PKTHDR) ? MHLEN :				\
1193 	 MLEN)
1194 
1195 /*
1196  * Set the m_data pointer of a newly allocated mbuf to place an object of the
1197  * specified size at the end of the mbuf, longword aligned.
1198  *
1199  * NB: Historically, we had M_ALIGN(), MH_ALIGN(), and MEXT_ALIGN() as
1200  * separate macros, each asserting that it was called at the proper moment.
1201  * This required callers to themselves test the storage type and call the
1202  * right one.  Rather than require callers to be aware of those layout
1203  * decisions, we centralize here.
1204  */
1205 static __inline void
1206 m_align(struct mbuf *m, int len)
1207 {
1208 #ifdef INVARIANTS
1209 	const char *msg = "%s: not a virgin mbuf";
1210 #endif
1211 	int adjust;
1212 
1213 	KASSERT(m->m_data == M_START(m), (msg, __func__));
1214 
1215 	adjust = M_SIZE(m) - len;
1216 	m->m_data += adjust &~ (sizeof(long)-1);
1217 }
1218 
1219 #define	M_ALIGN(m, len)		m_align(m, len)
1220 #define	MH_ALIGN(m, len)	m_align(m, len)
1221 #define	MEXT_ALIGN(m, len)	m_align(m, len)
1222 
1223 /*
1224  * Compute the amount of space available before the current start of data in
1225  * an mbuf.
1226  *
1227  * The M_WRITABLE() is a temporary, conservative safety measure: the burden
1228  * of checking writability of the mbuf data area rests solely with the caller.
1229  *
1230  * NB: In previous versions, M_LEADINGSPACE() would only check M_WRITABLE()
1231  * for mbufs with external storage.  We now allow mbuf-embedded data to be
1232  * read-only as well.
1233  */
1234 #define	M_LEADINGSPACE(m)						\
1235 	(M_WRITABLE(m) ? ((m)->m_data - M_START(m)) : 0)
1236 
1237 /*
1238  * So M_TRAILINGROOM() is for when you want to know how much space
1239  * would be there if it was writable. This can be used to
1240  * detect changes in mbufs by knowing the value at one point
1241  * and then being able to compare it later to the current M_TRAILINGROOM().
1242  * The TRAILINGSPACE() macro is not suitable for this since an mbuf
1243  * at one point might not be writable and then later it becomes writable
1244  * even though the space at the back of it has not changed.
1245  */
1246 #define M_TRAILINGROOM(m) ((M_START(m) + M_SIZE(m)) - ((m)->m_data + (m)->m_len))
1247 /*
1248  * Compute the amount of space available after the end of data in an mbuf.
1249  *
1250  * The M_WRITABLE() is a temporary, conservative safety measure: the burden
1251  * of checking writability of the mbuf data area rests solely with the caller.
1252  *
1253  * NB: In previous versions, M_TRAILINGSPACE() would only check M_WRITABLE()
1254  * for mbufs with external storage.  We now allow mbuf-embedded data to be
1255  * read-only as well.
1256  */
1257 #define	M_TRAILINGSPACE(m) (M_WRITABLE(m) ? M_TRAILINGROOM(m) : 0)
1258 
1259 /*
1260  * Arrange to prepend space of size plen to mbuf m.  If a new mbuf must be
1261  * allocated, how specifies whether to wait.  If the allocation fails, the
1262  * original mbuf chain is freed and m is set to NULL.
1263  */
1264 #define	M_PREPEND(m, plen, how) do {					\
1265 	struct mbuf **_mmp = &(m);					\
1266 	struct mbuf *_mm = *_mmp;					\
1267 	int _mplen = (plen);						\
1268 	int __mhow = (how);						\
1269 									\
1270 	MBUF_CHECKSLEEP(how);						\
1271 	if (M_LEADINGSPACE(_mm) >= _mplen) {				\
1272 		_mm->m_data -= _mplen;					\
1273 		_mm->m_len += _mplen;					\
1274 	} else								\
1275 		_mm = m_prepend(_mm, _mplen, __mhow);			\
1276 	if (_mm != NULL && _mm->m_flags & M_PKTHDR)			\
1277 		_mm->m_pkthdr.len += _mplen;				\
1278 	*_mmp = _mm;							\
1279 } while (0)
1280 
1281 /*
1282  * Change mbuf to new type.  This is a relatively expensive operation and
1283  * should be avoided.
1284  */
1285 #define	MCHTYPE(m, t)	m_chtype((m), (t))
1286 
1287 /* Return the rcvif of a packet header. */
1288 static __inline struct ifnet *
1289 m_rcvif(struct mbuf *m)
1290 {
1291 
1292 	M_ASSERTPKTHDR(m);
1293 	if (m->m_pkthdr.csum_flags & CSUM_SND_TAG)
1294 		return (NULL);
1295 	return (m->m_pkthdr.rcvif);
1296 }
1297 
1298 /* Length to m_copy to copy all. */
1299 #define	M_COPYALL	1000000000
1300 
1301 extern u_int		max_linkhdr;	/* Largest link-level header */
1302 extern u_int		max_hdr;	/* Largest link + protocol header */
1303 extern u_int		max_protohdr;	/* Largest protocol header */
1304 void max_linkhdr_grow(u_int);
1305 void max_protohdr_grow(u_int);
1306 
1307 extern int		nmbclusters;	/* Maximum number of clusters */
1308 extern bool		mb_use_ext_pgs;	/* Use ext_pgs for sendfile */
1309 
1310 /*-
1311  * Network packets may have annotations attached by affixing a list of
1312  * "packet tags" to the pkthdr structure.  Packet tags are dynamically
1313  * allocated semi-opaque data structures that have a fixed header
1314  * (struct m_tag) that specifies the size of the memory block and a
1315  * <cookie,type> pair that identifies it.  The cookie is a 32-bit unique
1316  * unsigned value used to identify a module or ABI.  By convention this value
1317  * is chosen as the date+time that the module is created, expressed as the
1318  * number of seconds since the epoch (e.g., using date -u +'%s').  The type
1319  * value is an ABI/module-specific value that identifies a particular
1320  * annotation and is private to the module.  For compatibility with systems
1321  * like OpenBSD that define packet tags w/o an ABI/module cookie, the value
1322  * PACKET_ABI_COMPAT is used to implement m_tag_get and m_tag_find
1323  * compatibility shim functions and several tag types are defined below.
1324  * Users that do not require compatibility should use a private cookie value
1325  * so that packet tag-related definitions can be maintained privately.
1326  *
1327  * Note that the packet tag returned by m_tag_alloc has the default memory
1328  * alignment implemented by malloc.  To reference private data one can use a
1329  * construct like:
1330  *
1331  *	struct m_tag *mtag = m_tag_alloc(...);
1332  *	struct foo *p = (struct foo *)(mtag+1);
1333  *
1334  * if the alignment of struct m_tag is sufficient for referencing members of
1335  * struct foo.  Otherwise it is necessary to embed struct m_tag within the
1336  * private data structure to insure proper alignment; e.g.,
1337  *
1338  *	struct foo {
1339  *		struct m_tag	tag;
1340  *		...
1341  *	};
1342  *	struct foo *p = (struct foo *) m_tag_alloc(...);
1343  *	struct m_tag *mtag = &p->tag;
1344  */
1345 
1346 /*
1347  * Persistent tags stay with an mbuf until the mbuf is reclaimed.  Otherwise
1348  * tags are expected to ``vanish'' when they pass through a network
1349  * interface.  For most interfaces this happens normally as the tags are
1350  * reclaimed when the mbuf is free'd.  However in some special cases
1351  * reclaiming must be done manually.  An example is packets that pass through
1352  * the loopback interface.  Also, one must be careful to do this when
1353  * ``turning around'' packets (e.g., icmp_reflect).
1354  *
1355  * To mark a tag persistent bit-or this flag in when defining the tag id.
1356  * The tag will then be treated as described above.
1357  */
1358 #define	MTAG_PERSISTENT				0x800
1359 
1360 #define	PACKET_TAG_NONE				0  /* Nadda */
1361 
1362 /* Packet tags for use with PACKET_ABI_COMPAT. */
1363 #define	PACKET_TAG_IPSEC_IN_DONE		1  /* IPsec applied, in */
1364 #define	PACKET_TAG_IPSEC_OUT_DONE		2  /* IPsec applied, out */
1365 #define	PACKET_TAG_IPSEC_IN_CRYPTO_DONE		3  /* NIC IPsec crypto done */
1366 #define	PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED	4  /* NIC IPsec crypto req'ed */
1367 #define	PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO	5  /* NIC notifies IPsec */
1368 #define	PACKET_TAG_IPSEC_PENDING_TDB		6  /* Reminder to do IPsec */
1369 #define	PACKET_TAG_BRIDGE			7  /* Bridge processing done */
1370 #define	PACKET_TAG_GIF				8  /* GIF processing done */
1371 #define	PACKET_TAG_GRE				9  /* GRE processing done */
1372 #define	PACKET_TAG_IN_PACKET_CHECKSUM		10 /* NIC checksumming done */
1373 #define	PACKET_TAG_ENCAP			11 /* Encap.  processing */
1374 #define	PACKET_TAG_IPSEC_SOCKET			12 /* IPSEC socket ref */
1375 #define	PACKET_TAG_IPSEC_HISTORY		13 /* IPSEC history */
1376 #define	PACKET_TAG_IPV6_INPUT			14 /* IPV6 input processing */
1377 #define	PACKET_TAG_DUMMYNET			15 /* dummynet info */
1378 #define	PACKET_TAG_DIVERT			17 /* divert info */
1379 #define	PACKET_TAG_IPFORWARD			18 /* ipforward info */
1380 #define	PACKET_TAG_MACLABEL	(19 | MTAG_PERSISTENT) /* MAC label */
1381 #define	PACKET_TAG_PF				21 /* PF/ALTQ information */
1382 /* was	PACKET_TAG_RTSOCKFAM			25    rtsock sa family */
1383 #define	PACKET_TAG_IPOPTIONS			27 /* Saved IP options */
1384 #define	PACKET_TAG_CARP				28 /* CARP info */
1385 #define	PACKET_TAG_IPSEC_NAT_T_PORTS		29 /* two uint16_t */
1386 #define	PACKET_TAG_ND_OUTGOING			30 /* ND outgoing */
1387 #define	PACKET_TAG_PF_REASSEMBLED		31
1388 
1389 /* Specific cookies and tags. */
1390 
1391 /* Packet tag routines. */
1392 struct m_tag	*m_tag_alloc(uint32_t, uint16_t, int, int);
1393 void		 m_tag_delete(struct mbuf *, struct m_tag *);
1394 void		 m_tag_delete_chain(struct mbuf *, struct m_tag *);
1395 void		 m_tag_free_default(struct m_tag *);
1396 struct m_tag	*m_tag_locate(struct mbuf *, uint32_t, uint16_t,
1397     struct m_tag *);
1398 struct m_tag	*m_tag_copy(struct m_tag *, int);
1399 int		 m_tag_copy_chain(struct mbuf *, const struct mbuf *, int);
1400 void		 m_tag_delete_nonpersistent(struct mbuf *);
1401 
1402 /*
1403  * Initialize the list of tags associated with an mbuf.
1404  */
1405 static __inline void
1406 m_tag_init(struct mbuf *m)
1407 {
1408 
1409 	SLIST_INIT(&m->m_pkthdr.tags);
1410 }
1411 
1412 /*
1413  * Set up the contents of a tag.  Note that this does not fill in the free
1414  * method; the caller is expected to do that.
1415  *
1416  * XXX probably should be called m_tag_init, but that was already taken.
1417  */
1418 static __inline void
1419 m_tag_setup(struct m_tag *t, uint32_t cookie, uint16_t type, int len)
1420 {
1421 
1422 	t->m_tag_id = type;
1423 	t->m_tag_len = len;
1424 	t->m_tag_cookie = cookie;
1425 }
1426 
1427 /*
1428  * Reclaim resources associated with a tag.
1429  */
1430 static __inline void
1431 m_tag_free(struct m_tag *t)
1432 {
1433 
1434 	(*t->m_tag_free)(t);
1435 }
1436 
1437 /*
1438  * Return the first tag associated with an mbuf.
1439  */
1440 static __inline struct m_tag *
1441 m_tag_first(struct mbuf *m)
1442 {
1443 
1444 	return (SLIST_FIRST(&m->m_pkthdr.tags));
1445 }
1446 
1447 /*
1448  * Return the next tag in the list of tags associated with an mbuf.
1449  */
1450 static __inline struct m_tag *
1451 m_tag_next(struct mbuf *m __unused, struct m_tag *t)
1452 {
1453 
1454 	return (SLIST_NEXT(t, m_tag_link));
1455 }
1456 
1457 /*
1458  * Prepend a tag to the list of tags associated with an mbuf.
1459  */
1460 static __inline void
1461 m_tag_prepend(struct mbuf *m, struct m_tag *t)
1462 {
1463 
1464 	SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link);
1465 }
1466 
1467 /*
1468  * Unlink a tag from the list of tags associated with an mbuf.
1469  */
1470 static __inline void
1471 m_tag_unlink(struct mbuf *m, struct m_tag *t)
1472 {
1473 
1474 	SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link);
1475 }
1476 
1477 /* These are for OpenBSD compatibility. */
1478 #define	MTAG_ABI_COMPAT		0		/* compatibility ABI */
1479 
1480 static __inline struct m_tag *
1481 m_tag_get(uint16_t type, int length, int wait)
1482 {
1483 	return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait));
1484 }
1485 
1486 static __inline struct m_tag *
1487 m_tag_find(struct mbuf *m, uint16_t type, struct m_tag *start)
1488 {
1489 	return (SLIST_EMPTY(&m->m_pkthdr.tags) ? (struct m_tag *)NULL :
1490 	    m_tag_locate(m, MTAG_ABI_COMPAT, type, start));
1491 }
1492 
1493 static inline struct m_snd_tag *
1494 m_snd_tag_ref(struct m_snd_tag *mst)
1495 {
1496 
1497 	refcount_acquire(&mst->refcount);
1498 	return (mst);
1499 }
1500 
1501 static inline void
1502 m_snd_tag_rele(struct m_snd_tag *mst)
1503 {
1504 
1505 	if (refcount_release(&mst->refcount))
1506 		m_snd_tag_destroy(mst);
1507 }
1508 
1509 static __inline struct mbuf *
1510 m_free(struct mbuf *m)
1511 {
1512 	struct mbuf *n = m->m_next;
1513 
1514 	MBUF_PROBE1(m__free, m);
1515 	if ((m->m_flags & (M_PKTHDR|M_NOFREE)) == (M_PKTHDR|M_NOFREE))
1516 		m_tag_delete_chain(m, NULL);
1517 	if (m->m_flags & M_PKTHDR && m->m_pkthdr.csum_flags & CSUM_SND_TAG)
1518 		m_snd_tag_rele(m->m_pkthdr.snd_tag);
1519 	if (m->m_flags & M_EXTPG)
1520 		mb_free_extpg(m);
1521 	else if (m->m_flags & M_EXT)
1522 		mb_free_ext(m);
1523 	else if ((m->m_flags & M_NOFREE) == 0)
1524 		uma_zfree(zone_mbuf, m);
1525 	return (n);
1526 }
1527 
1528 static __inline int
1529 rt_m_getfib(struct mbuf *m)
1530 {
1531 	KASSERT(m->m_flags & M_PKTHDR , ("Attempt to get FIB from non header mbuf."));
1532 	return (m->m_pkthdr.fibnum);
1533 }
1534 
1535 #define M_GETFIB(_m)   rt_m_getfib(_m)
1536 
1537 #define M_SETFIB(_m, _fib) do {						\
1538         KASSERT((_m)->m_flags & M_PKTHDR, ("Attempt to set FIB on non header mbuf."));	\
1539 	((_m)->m_pkthdr.fibnum) = (_fib);				\
1540 } while (0)
1541 
1542 /* flags passed as first argument for "m_xxx_tcpip_hash()" */
1543 #define	MBUF_HASHFLAG_L2	(1 << 2)
1544 #define	MBUF_HASHFLAG_L3	(1 << 3)
1545 #define	MBUF_HASHFLAG_L4	(1 << 4)
1546 
1547 /* mbuf hashing helper routines */
1548 uint32_t	m_ether_tcpip_hash_init(void);
1549 uint32_t	m_ether_tcpip_hash(const uint32_t, const struct mbuf *, uint32_t);
1550 uint32_t	m_infiniband_tcpip_hash_init(void);
1551 uint32_t	m_infiniband_tcpip_hash(const uint32_t, const struct mbuf *, uint32_t);
1552 
1553 #ifdef MBUF_PROFILING
1554  void m_profile(struct mbuf *m);
1555  #define M_PROFILE(m) m_profile(m)
1556 #else
1557  #define M_PROFILE(m)
1558 #endif
1559 
1560 struct mbufq {
1561 	STAILQ_HEAD(, mbuf)	mq_head;
1562 	int			mq_len;
1563 	int			mq_maxlen;
1564 };
1565 
1566 static inline void
1567 mbufq_init(struct mbufq *mq, int maxlen)
1568 {
1569 
1570 	STAILQ_INIT(&mq->mq_head);
1571 	mq->mq_maxlen = maxlen;
1572 	mq->mq_len = 0;
1573 }
1574 
1575 static inline struct mbuf *
1576 mbufq_flush(struct mbufq *mq)
1577 {
1578 	struct mbuf *m;
1579 
1580 	m = STAILQ_FIRST(&mq->mq_head);
1581 	STAILQ_INIT(&mq->mq_head);
1582 	mq->mq_len = 0;
1583 	return (m);
1584 }
1585 
1586 static inline void
1587 mbufq_drain(struct mbufq *mq)
1588 {
1589 	struct mbuf *m, *n;
1590 
1591 	n = mbufq_flush(mq);
1592 	while ((m = n) != NULL) {
1593 		n = STAILQ_NEXT(m, m_stailqpkt);
1594 		m_freem(m);
1595 	}
1596 }
1597 
1598 static inline struct mbuf *
1599 mbufq_first(const struct mbufq *mq)
1600 {
1601 
1602 	return (STAILQ_FIRST(&mq->mq_head));
1603 }
1604 
1605 static inline struct mbuf *
1606 mbufq_last(const struct mbufq *mq)
1607 {
1608 
1609 	return (STAILQ_LAST(&mq->mq_head, mbuf, m_stailqpkt));
1610 }
1611 
1612 static inline int
1613 mbufq_full(const struct mbufq *mq)
1614 {
1615 
1616 	return (mq->mq_maxlen > 0 && mq->mq_len >= mq->mq_maxlen);
1617 }
1618 
1619 static inline int
1620 mbufq_len(const struct mbufq *mq)
1621 {
1622 
1623 	return (mq->mq_len);
1624 }
1625 
1626 static inline int
1627 mbufq_enqueue(struct mbufq *mq, struct mbuf *m)
1628 {
1629 
1630 	if (mbufq_full(mq))
1631 		return (ENOBUFS);
1632 	STAILQ_INSERT_TAIL(&mq->mq_head, m, m_stailqpkt);
1633 	mq->mq_len++;
1634 	return (0);
1635 }
1636 
1637 static inline struct mbuf *
1638 mbufq_dequeue(struct mbufq *mq)
1639 {
1640 	struct mbuf *m;
1641 
1642 	m = STAILQ_FIRST(&mq->mq_head);
1643 	if (m) {
1644 		STAILQ_REMOVE_HEAD(&mq->mq_head, m_stailqpkt);
1645 		m->m_nextpkt = NULL;
1646 		mq->mq_len--;
1647 	}
1648 	return (m);
1649 }
1650 
1651 static inline void
1652 mbufq_prepend(struct mbufq *mq, struct mbuf *m)
1653 {
1654 
1655 	STAILQ_INSERT_HEAD(&mq->mq_head, m, m_stailqpkt);
1656 	mq->mq_len++;
1657 }
1658 
1659 /*
1660  * Note: this doesn't enforce the maximum list size for dst.
1661  */
1662 static inline void
1663 mbufq_concat(struct mbufq *mq_dst, struct mbufq *mq_src)
1664 {
1665 
1666 	mq_dst->mq_len += mq_src->mq_len;
1667 	STAILQ_CONCAT(&mq_dst->mq_head, &mq_src->mq_head);
1668 	mq_src->mq_len = 0;
1669 }
1670 
1671 #ifdef _SYS_TIMESPEC_H_
1672 static inline void
1673 mbuf_tstmp2timespec(struct mbuf *m, struct timespec *ts)
1674 {
1675 
1676 	KASSERT((m->m_flags & M_PKTHDR) != 0, ("mbuf %p no M_PKTHDR", m));
1677 	KASSERT((m->m_flags & (M_TSTMP|M_TSTMP_LRO)) != 0,
1678 	    ("mbuf %p no M_TSTMP or M_TSTMP_LRO", m));
1679 	ts->tv_sec = m->m_pkthdr.rcv_tstmp / 1000000000;
1680 	ts->tv_nsec = m->m_pkthdr.rcv_tstmp % 1000000000;
1681 }
1682 #endif
1683 
1684 static inline void
1685 mbuf_tstmp2timeval(struct mbuf *m, struct timeval *tv)
1686 {
1687 
1688 	KASSERT((m->m_flags & M_PKTHDR) != 0, ("mbuf %p no M_PKTHDR", m));
1689 	KASSERT((m->m_flags & (M_TSTMP|M_TSTMP_LRO)) != 0,
1690 	    ("mbuf %p no M_TSTMP or M_TSTMP_LRO", m));
1691 	tv->tv_sec = m->m_pkthdr.rcv_tstmp / 1000000000;
1692 	tv->tv_usec = (m->m_pkthdr.rcv_tstmp % 1000000000) / 1000;
1693 }
1694 
1695 #ifdef DEBUGNET
1696 /* Invoked from the debugnet client code. */
1697 void	debugnet_mbuf_drain(void);
1698 void	debugnet_mbuf_start(void);
1699 void	debugnet_mbuf_finish(void);
1700 void	debugnet_mbuf_reinit(int nmbuf, int nclust, int clsize);
1701 #endif
1702 
1703 static inline bool
1704 mbuf_has_tls_session(struct mbuf *m)
1705 {
1706 
1707 	if (m->m_flags & M_EXTPG) {
1708 		if (m->m_epg_tls != NULL) {
1709 			return (true);
1710 		}
1711 	}
1712 	return (false);
1713 }
1714 
1715 #endif /* _KERNEL */
1716 #endif /* !_SYS_MBUF_H_ */
1717