xref: /freebsd/sys/sys/mbuf.h (revision 3673801f)
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 
33 #ifndef _SYS_MBUF_H_
34 #define	_SYS_MBUF_H_
35 
36 /* XXX: These includes suck. Sorry! */
37 #include <sys/queue.h>
38 #ifdef _KERNEL
39 #include <sys/systm.h>
40 #include <sys/refcount.h>
41 #include <vm/uma.h>
42 
43 #include <sys/sdt.h>
44 
45 #define	MBUF_PROBE1(probe, arg0)					\
46 	SDT_PROBE1(sdt, , , probe, arg0)
47 #define	MBUF_PROBE2(probe, arg0, arg1)					\
48 	SDT_PROBE2(sdt, , , probe, arg0, arg1)
49 #define	MBUF_PROBE3(probe, arg0, arg1, arg2)				\
50 	SDT_PROBE3(sdt, , , probe, arg0, arg1, arg2)
51 #define	MBUF_PROBE4(probe, arg0, arg1, arg2, arg3)			\
52 	SDT_PROBE4(sdt, , , probe, arg0, arg1, arg2, arg3)
53 #define	MBUF_PROBE5(probe, arg0, arg1, arg2, arg3, arg4)		\
54 	SDT_PROBE5(sdt, , , probe, arg0, arg1, arg2, arg3, arg4)
55 
56 SDT_PROBE_DECLARE(sdt, , , m__init);
57 SDT_PROBE_DECLARE(sdt, , , m__gethdr_raw);
58 SDT_PROBE_DECLARE(sdt, , , m__gethdr);
59 SDT_PROBE_DECLARE(sdt, , , m__get_raw);
60 SDT_PROBE_DECLARE(sdt, , , m__get);
61 SDT_PROBE_DECLARE(sdt, , , m__getcl);
62 SDT_PROBE_DECLARE(sdt, , , m__getjcl);
63 SDT_PROBE_DECLARE(sdt, , , m__clget);
64 SDT_PROBE_DECLARE(sdt, , , m__cljget);
65 SDT_PROBE_DECLARE(sdt, , , m__cljset);
66 SDT_PROBE_DECLARE(sdt, , , m__free);
67 SDT_PROBE_DECLARE(sdt, , , m__freem);
68 SDT_PROBE_DECLARE(sdt, , , m__freemp);
69 
70 #endif /* _KERNEL */
71 
72 /*
73  * Mbufs are of a single size, MSIZE (sys/param.h), which includes overhead.
74  * An mbuf may add a single "mbuf cluster" of size MCLBYTES (also in
75  * sys/param.h), which has no additional overhead and is used instead of the
76  * internal data area; this is done when at least MINCLSIZE of data must be
77  * stored.  Additionally, it is possible to allocate a separate buffer
78  * externally and attach it to the mbuf in a way similar to that of mbuf
79  * clusters.
80  *
81  * NB: These calculation do not take actual compiler-induced alignment and
82  * padding inside the complete struct mbuf into account.  Appropriate
83  * attention is required when changing members of struct mbuf.
84  *
85  * MLEN is data length in a normal mbuf.
86  * MHLEN is data length in an mbuf with pktheader.
87  * MINCLSIZE is a smallest amount of data that should be put into cluster.
88  *
89  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
90  * they are sensible.
91  */
92 struct mbuf;
93 #define	MHSIZE		offsetof(struct mbuf, m_dat)
94 #define	MPKTHSIZE	offsetof(struct mbuf, m_pktdat)
95 #define	MLEN		((int)(MSIZE - MHSIZE))
96 #define	MHLEN		((int)(MSIZE - MPKTHSIZE))
97 #define	MINCLSIZE	(MHLEN + 1)
98 #define	M_NODOM		255
99 
100 #ifdef _KERNEL
101 /*-
102  * Macro for type conversion: convert mbuf pointer to data pointer of correct
103  * type:
104  *
105  * mtod(m, t)	-- Convert mbuf pointer to data pointer of correct type.
106  * mtodo(m, o) -- Same as above but with offset 'o' into data.
107  */
108 #define	mtod(m, t)	((t)((m)->m_data))
109 #define	mtodo(m, o)	((void *)(((m)->m_data) + (o)))
110 
111 /*
112  * Argument structure passed to UMA routines during mbuf and packet
113  * allocations.
114  */
115 struct mb_args {
116 	int	flags;	/* Flags for mbuf being allocated */
117 	short	type;	/* Type of mbuf being allocated */
118 };
119 #endif /* _KERNEL */
120 
121 /*
122  * Packet tag structure (see below for details).
123  */
124 struct m_tag {
125 	SLIST_ENTRY(m_tag)	m_tag_link;	/* List of packet tags */
126 	u_int16_t		m_tag_id;	/* Tag ID */
127 	u_int16_t		m_tag_len;	/* Length of data */
128 	u_int32_t		m_tag_cookie;	/* ABI/Module ID */
129 	void			(*m_tag_free)(struct m_tag *);
130 };
131 
132 /*
133  * Static network interface owned tag.
134  * Allocated through ifp->if_snd_tag_alloc().
135  */
136 struct if_snd_tag_sw;
137 
138 struct m_snd_tag {
139 	struct ifnet *ifp;		/* network interface tag belongs to */
140 	const struct if_snd_tag_sw *sw;
141 	volatile u_int refcount;
142 };
143 
144 /*
145  * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set.
146  * Size ILP32: 56
147  *	 LP64: 64
148  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
149  * they are correct.
150  */
151 struct pkthdr {
152 	union {
153 		struct m_snd_tag *snd_tag;	/* send tag, if any */
154 		struct ifnet	*rcvif;		/* rcv interface */
155 		struct {
156 			uint16_t rcvidx;	/* rcv interface index ... */
157 			uint16_t rcvgen;	/* ... and generation count */
158 		};
159 	};
160 	union {
161 		struct ifnet	*leaf_rcvif;	/* leaf rcv interface */
162 		struct {
163 			uint16_t leaf_rcvidx;	/* leaf rcv interface index ... */
164 			uint16_t leaf_rcvgen;	/* ... and generation count */
165 		};
166 	};
167 	SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */
168 	int32_t		 len;		/* total packet length */
169 
170 	/* Layer crossing persistent information. */
171 	uint32_t	 flowid;	/* packet's 4-tuple system */
172 	uint32_t	 csum_flags;	/* checksum and offload features */
173 	uint16_t	 fibnum;	/* this packet should use this fib */
174 	uint8_t		 numa_domain;	/* NUMA domain of recvd pkt */
175 	uint8_t		 rsstype;	/* hash type */
176 #if !defined(__LP64__)
177 	uint32_t	 pad;		/* pad for 64bit alignment */
178 #endif
179 	union {
180 		uint64_t	rcv_tstmp;	/* timestamp in ns */
181 		struct {
182 			uint8_t		 l2hlen;	/* layer 2 hdr len */
183 			uint8_t		 l3hlen;	/* layer 3 hdr len */
184 			uint8_t		 l4hlen;	/* layer 4 hdr len */
185 			uint8_t		 l5hlen;	/* layer 5 hdr len */
186 			uint8_t		 inner_l2hlen;
187 			uint8_t		 inner_l3hlen;
188 			uint8_t		 inner_l4hlen;
189 			uint8_t		 inner_l5hlen;
190 		};
191 	};
192 	union {
193 		uint8_t  eight[8];
194 		uint16_t sixteen[4];
195 		uint32_t thirtytwo[2];
196 		uint64_t sixtyfour[1];
197 		uintptr_t unintptr[1];
198 		void	*ptr;
199 	} PH_per;
200 
201 	/* Layer specific non-persistent local storage for reassembly, etc. */
202 	union {
203 		union {
204 			uint8_t  eight[8];
205 			uint16_t sixteen[4];
206 			uint32_t thirtytwo[2];
207 			uint64_t sixtyfour[1];
208 			uintptr_t unintptr[1];
209 			void 	*ptr;
210 		} PH_loc;
211 		/* Upon allocation: total packet memory consumption. */
212 		u_int	memlen;
213 	};
214 };
215 #define	ether_vtag	PH_per.sixteen[0]
216 #define tcp_tun_port	PH_per.sixteen[0] /* outbound */
217 #define	vt_nrecs	PH_per.sixteen[0]	  /* mld and v6-ND */
218 #define	tso_segsz	PH_per.sixteen[1] /* inbound after LRO */
219 #define	lro_nsegs	tso_segsz	  /* inbound after LRO */
220 #define	csum_data	PH_per.thirtytwo[1] /* inbound from hardware up */
221 #define	lro_tcp_d_len	PH_loc.sixteen[0] /* inbound during LRO (no reassembly) */
222 #define	lro_tcp_d_csum	PH_loc.sixteen[1] /* inbound during LRO (no reassembly) */
223 #define	lro_tcp_h_off	PH_loc.sixteen[2] /* inbound during LRO (no reassembly) */
224 #define	lro_etype	PH_loc.sixteen[3] /* inbound during LRO (no reassembly) */
225 /* Note PH_loc is used during IP reassembly (all 8 bytes as a ptr) */
226 
227 /*
228  * TLS records for TLS 1.0-1.2 can have the following header lengths:
229  * - 5 (AES-CBC with implicit IV)
230  * - 21 (AES-CBC with explicit IV)
231  * - 13 (AES-GCM with 8 byte explicit IV)
232  */
233 #define	MBUF_PEXT_HDR_LEN	23
234 
235 /*
236  * TLS records for TLS 1.0-1.2 can have the following maximum trailer
237  * lengths:
238  * - 16 (AES-GCM)
239  * - 36 (AES-CBC with SHA1 and up to 16 bytes of padding)
240  * - 48 (AES-CBC with SHA2-256 and up to 16 bytes of padding)
241  * - 64 (AES-CBC with SHA2-384 and up to 16 bytes of padding)
242  */
243 #define	MBUF_PEXT_TRAIL_LEN	64
244 
245 #if defined(__LP64__)
246 #define MBUF_PEXT_MAX_PGS (40 / sizeof(vm_paddr_t))
247 #else
248 #define MBUF_PEXT_MAX_PGS (64 / sizeof(vm_paddr_t))
249 #endif
250 
251 #define	MBUF_PEXT_MAX_BYTES						\
252     (MBUF_PEXT_MAX_PGS * PAGE_SIZE + MBUF_PEXT_HDR_LEN + MBUF_PEXT_TRAIL_LEN)
253 
254 struct ktls_session;
255 struct socket;
256 
257 /*
258  * Description of external storage mapped into mbuf; valid only if M_EXT is
259  * set.
260  * Size ILP32: 28
261  *	 LP64: 48
262  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
263  * they are correct.
264  */
265 typedef	void m_ext_free_t(struct mbuf *);
266 struct m_ext {
267 	union {
268 		/*
269 		 * If EXT_FLAG_EMBREF is set, then we use refcount in the
270 		 * mbuf, the 'ext_count' member.  Otherwise, we have a
271 		 * shadow copy and we use pointer 'ext_cnt'.  The original
272 		 * mbuf is responsible to carry the pointer to free routine
273 		 * and its arguments.  They aren't copied into shadows in
274 		 * mb_dupcl() to avoid dereferencing next cachelines.
275 		 */
276 		volatile u_int	 ext_count;
277 		volatile u_int	*ext_cnt;
278 	};
279 	uint32_t	 ext_size;	/* size of buffer, for ext_free */
280 	uint32_t	 ext_type:8,	/* type of external storage */
281 			 ext_flags:24;	/* external storage mbuf flags */
282 	union {
283 		struct {
284 			/*
285 			 * Regular M_EXT mbuf:
286 			 * o ext_buf always points to the external buffer.
287 			 * o ext_free (below) and two optional arguments
288 			 *   ext_arg1 and ext_arg2 store the free context for
289 			 *   the external storage.  They are set only in the
290 			 *   refcount carrying mbuf, the one with
291 			 *   EXT_FLAG_EMBREF flag, with exclusion for
292 			 *   EXT_EXTREF type, where the free context is copied
293 			 *   into all mbufs that use same external storage.
294 			 */
295 			char 	*ext_buf;	/* start of buffer */
296 #define	m_ext_copylen	offsetof(struct m_ext, ext_arg2)
297 			void	*ext_arg2;
298 		};
299 		struct {
300 			/*
301 			 * Multi-page M_EXTPG mbuf:
302 			 * o extpg_pa - page vector.
303 			 * o extpg_trail and extpg_hdr - TLS trailer and
304 			 *   header.
305 			 * Uses ext_free and may also use ext_arg1.
306 			 */
307 			vm_paddr_t	extpg_pa[MBUF_PEXT_MAX_PGS];
308 			char		extpg_trail[MBUF_PEXT_TRAIL_LEN];
309 			char		extpg_hdr[MBUF_PEXT_HDR_LEN];
310 			/* Pretend these 3 fields are part of mbuf itself. */
311 #define	m_epg_pa	m_ext.extpg_pa
312 #define	m_epg_trail	m_ext.extpg_trail
313 #define	m_epg_hdr	m_ext.extpg_hdr
314 #define	m_epg_ext_copylen	offsetof(struct m_ext, ext_free)
315 		};
316 	};
317 	/*
318 	 * Free method and optional argument pointer, both
319 	 * used by M_EXT and M_EXTPG.
320 	 */
321 	m_ext_free_t	*ext_free;
322 	void		*ext_arg1;
323 };
324 
325 /*
326  * The core of the mbuf object along with some shortcut defines for practical
327  * purposes.
328  */
329 struct mbuf {
330 	/*
331 	 * Header present at the beginning of every mbuf.
332 	 * Size ILP32: 24
333 	 *      LP64: 32
334 	 * Compile-time assertions in uipc_mbuf.c test these values to ensure
335 	 * that they are correct.
336 	 */
337 	union {	/* next buffer in chain */
338 		struct mbuf		*m_next;
339 		SLIST_ENTRY(mbuf)	m_slist;
340 		STAILQ_ENTRY(mbuf)	m_stailq;
341 	};
342 	union {	/* next chain in queue/record */
343 		struct mbuf		*m_nextpkt;
344 		SLIST_ENTRY(mbuf)	m_slistpkt;
345 		STAILQ_ENTRY(mbuf)	m_stailqpkt;
346 	};
347 	caddr_t		 m_data;	/* location of data */
348 	int32_t		 m_len;		/* amount of data in this mbuf */
349 	uint32_t	 m_type:8,	/* type of data in this mbuf */
350 			 m_flags:24;	/* flags; see below */
351 #if !defined(__LP64__)
352 	uint32_t	 m_pad;		/* pad for 64bit alignment */
353 #endif
354 
355 	/*
356 	 * A set of optional headers (packet header, external storage header)
357 	 * and internal data storage.  Historically, these arrays were sized
358 	 * to MHLEN (space left after a packet header) and MLEN (space left
359 	 * after only a regular mbuf header); they are now variable size in
360 	 * order to support future work on variable-size mbufs.
361 	 */
362 	union {
363 		struct {
364 			union {
365 				/* M_PKTHDR set. */
366 				struct pkthdr	m_pkthdr;
367 
368 				/* M_EXTPG set.
369 				 * Multi-page M_EXTPG mbuf has its meta data
370 				 * split between the below anonymous structure
371 				 * and m_ext.  It carries vector of pages,
372 				 * optional header and trailer char vectors
373 				 * and pointers to socket/TLS data.
374 				 */
375 #define	m_epg_startcopy		m_epg_npgs
376 #define	m_epg_endcopy		m_epg_stailq
377 				struct {
378 					/* Overall count of pages and count of
379 					 * pages with I/O pending. */
380 					uint8_t	m_epg_npgs;
381 					uint8_t	m_epg_nrdy;
382 					/* TLS header and trailer lengths.
383 					 * The data itself resides in m_ext. */
384 					uint8_t	m_epg_hdrlen;
385 					uint8_t	m_epg_trllen;
386 					/* Offset into 1st page and length of
387 					 * data in the last page. */
388 					uint16_t m_epg_1st_off;
389 					uint16_t m_epg_last_len;
390 					uint8_t	m_epg_flags;
391 #define	EPG_FLAG_ANON	0x1	/* Data can be encrypted in place. */
392 #define	EPG_FLAG_2FREE	0x2	/* Scheduled for free. */
393 					uint8_t	m_epg_record_type;
394 					uint8_t	__spare[2];
395 					int	m_epg_enc_cnt;
396 					struct ktls_session *m_epg_tls;
397 					struct socket	*m_epg_so;
398 					uint64_t	m_epg_seqno;
399 					STAILQ_ENTRY(mbuf) m_epg_stailq;
400 				};
401 			};
402 			union {
403 				/* M_EXT or M_EXTPG set. */
404 				struct m_ext	m_ext;
405 				/* M_PKTHDR set, neither M_EXT nor M_EXTPG. */
406 				char		m_pktdat[0];
407 			};
408 		};
409 		char	m_dat[0];			/* !M_PKTHDR, !M_EXT */
410 	};
411 };
412 
413 #ifdef _KERNEL
414 static inline int
415 m_epg_pagelen(const struct mbuf *m, int pidx, int pgoff)
416 {
417 
418 	KASSERT(pgoff == 0 || pidx == 0,
419 	    ("page %d with non-zero offset %d in %p", pidx, pgoff, m));
420 
421 	if (pidx == m->m_epg_npgs - 1) {
422 		return (m->m_epg_last_len);
423 	} else {
424 		return (PAGE_SIZE - pgoff);
425 	}
426 }
427 
428 #ifdef INVARIANTS
429 #define	MCHECK(ex, msg)	KASSERT((ex),				\
430 	    ("Multi page mbuf %p with " #msg " at %s:%d",	\
431 	    m, __FILE__, __LINE__))
432 /*
433  * NB: This expects a non-empty buffer (npgs > 0 and
434  * last_pg_len > 0).
435  */
436 #define	MBUF_EXT_PGS_ASSERT_SANITY(m)	do {				\
437 	MCHECK(m->m_epg_npgs > 0, "no valid pages");		\
438 	MCHECK(m->m_epg_npgs <= nitems(m->m_epg_pa),		\
439 	    "too many pages");						\
440 	MCHECK(m->m_epg_nrdy <= m->m_epg_npgs,			\
441 	    "too many ready pages");					\
442 	MCHECK(m->m_epg_1st_off < PAGE_SIZE,			\
443 		"too large page offset");				\
444 	MCHECK(m->m_epg_last_len > 0, "zero last page length");	\
445 	MCHECK(m->m_epg_last_len <= PAGE_SIZE,			\
446 	    "too large last page length");				\
447 	if (m->m_epg_npgs == 1)					\
448 		MCHECK(m->m_epg_1st_off +			\
449 		    m->m_epg_last_len <=	 PAGE_SIZE,		\
450 		    "single page too large");				\
451 	MCHECK(m->m_epg_hdrlen <= sizeof(m->m_epg_hdr),		\
452 	    "too large header length");					\
453 	MCHECK(m->m_epg_trllen <= sizeof(m->m_epg_trail),	\
454 	    "too large header length");					\
455 } while (0)
456 #else
457 #define	MBUF_EXT_PGS_ASSERT_SANITY(m)	do {} while (0)
458 #endif
459 #endif
460 
461 /*
462  * mbuf flags of global significance and layer crossing.
463  * Those of only protocol/layer specific significance are to be mapped
464  * to M_PROTO[1-11] and cleared at layer handoff boundaries.
465  * NB: Limited to the lower 24 bits.
466  */
467 #define	M_EXT		0x00000001 /* has associated external storage */
468 #define	M_PKTHDR	0x00000002 /* start of record */
469 #define	M_EOR		0x00000004 /* end of record */
470 #define	M_RDONLY	0x00000008 /* associated data is marked read-only */
471 #define	M_BCAST		0x00000010 /* send/received as link-level broadcast */
472 #define	M_MCAST		0x00000020 /* send/received as link-level multicast */
473 #define	M_PROMISC	0x00000040 /* packet was not for us */
474 #define	M_VLANTAG	0x00000080 /* ether_vtag is valid */
475 #define	M_EXTPG		0x00000100 /* has array of unmapped pages and TLS */
476 #define	M_NOFREE	0x00000200 /* do not free mbuf, embedded in cluster */
477 #define	M_TSTMP		0x00000400 /* rcv_tstmp field is valid */
478 #define	M_TSTMP_HPREC	0x00000800 /* rcv_tstmp is high-prec, typically
479 				      hw-stamped on port (useful for IEEE 1588
480 				      and 802.1AS) */
481 #define M_TSTMP_LRO	0x00001000 /* Time LRO pushed in pkt is valid in (PH_loc) */
482 
483 #define	M_PROTO1	0x00002000 /* protocol-specific */
484 #define	M_PROTO2	0x00004000 /* protocol-specific */
485 #define	M_PROTO3	0x00008000 /* protocol-specific */
486 #define	M_PROTO4	0x00010000 /* protocol-specific */
487 #define	M_PROTO5	0x00020000 /* protocol-specific */
488 #define	M_PROTO6	0x00040000 /* protocol-specific */
489 #define	M_PROTO7	0x00080000 /* protocol-specific */
490 #define	M_PROTO8	0x00100000 /* protocol-specific */
491 #define	M_PROTO9	0x00200000 /* protocol-specific */
492 #define	M_PROTO10	0x00400000 /* protocol-specific */
493 #define	M_PROTO11	0x00800000 /* protocol-specific */
494 
495 /*
496  * Flags to purge when crossing layers.
497  */
498 #define	M_PROTOFLAGS \
499     (M_PROTO1|M_PROTO2|M_PROTO3|M_PROTO4|M_PROTO5|M_PROTO6|M_PROTO7|M_PROTO8|\
500      M_PROTO9|M_PROTO10|M_PROTO11)
501 
502 /*
503  * Flags preserved when copying m_pkthdr.
504  */
505 #define M_COPYFLAGS \
506     (M_PKTHDR|M_EOR|M_RDONLY|M_BCAST|M_MCAST|M_PROMISC|M_VLANTAG|M_TSTMP| \
507      M_TSTMP_HPREC|M_TSTMP_LRO|M_PROTOFLAGS)
508 
509 /*
510  * Flags preserved during demote.
511  */
512 #define	M_DEMOTEFLAGS \
513     (M_EXT | M_RDONLY | M_NOFREE | M_EXTPG)
514 
515 /*
516  * Mbuf flag description for use with printf(9) %b identifier.
517  */
518 #define	M_FLAG_BITS \
519     "\20\1M_EXT\2M_PKTHDR\3M_EOR\4M_RDONLY\5M_BCAST\6M_MCAST" \
520     "\7M_PROMISC\10M_VLANTAG\11M_EXTPG\12M_NOFREE\13M_TSTMP\14M_TSTMP_HPREC\15M_TSTMP_LRO"
521 #define	M_FLAG_PROTOBITS \
522     "\16M_PROTO1\17M_PROTO2\20M_PROTO3\21M_PROTO4" \
523     "\22M_PROTO5\23M_PROTO6\24M_PROTO7\25M_PROTO8\26M_PROTO9" \
524     "\27M_PROTO10\28M_PROTO11"
525 #define	M_FLAG_PRINTF (M_FLAG_BITS M_FLAG_PROTOBITS)
526 
527 /*
528  * Network interface cards are able to hash protocol fields (such as IPv4
529  * addresses and TCP port numbers) classify packets into flows.  These flows
530  * can then be used to maintain ordering while delivering packets to the OS
531  * via parallel input queues, as well as to provide a stateless affinity
532  * model.  NIC drivers can pass up the hash via m->m_pkthdr.flowid, and set
533  * m_flag fields to indicate how the hash should be interpreted by the
534  * network stack.
535  *
536  * Most NICs support RSS, which provides ordering and explicit affinity, and
537  * use the hash m_flag bits to indicate what header fields were covered by
538  * the hash.  M_HASHTYPE_OPAQUE and M_HASHTYPE_OPAQUE_HASH can be set by non-
539  * RSS cards or configurations that provide an opaque flow identifier, allowing
540  * for ordering and distribution without explicit affinity.  Additionally,
541  * M_HASHTYPE_OPAQUE_HASH indicates that the flow identifier has hash
542  * properties.
543  *
544  * The meaning of the IPV6_EX suffix:
545  * "o  Home address from the home address option in the IPv6 destination
546  *     options header.  If the extension header is not present, use the Source
547  *     IPv6 Address.
548  *  o  IPv6 address that is contained in the Routing-Header-Type-2 from the
549  *     associated extension header.  If the extension header is not present,
550  *     use the Destination IPv6 Address."
551  * Quoted from:
552  * https://docs.microsoft.com/en-us/windows-hardware/drivers/network/rss-hashing-types#ndishashipv6ex
553  */
554 #define	M_HASHTYPE_HASHPROP		0x80	/* has hash properties */
555 #define	M_HASHTYPE_INNER		0x40	/* calculated from inner headers */
556 #define	M_HASHTYPE_HASH(t)		(M_HASHTYPE_HASHPROP | (t))
557 /* Microsoft RSS standard hash types */
558 #define	M_HASHTYPE_NONE			0
559 #define	M_HASHTYPE_RSS_IPV4		M_HASHTYPE_HASH(1) /* IPv4 2-tuple */
560 #define	M_HASHTYPE_RSS_TCP_IPV4		M_HASHTYPE_HASH(2) /* TCPv4 4-tuple */
561 #define	M_HASHTYPE_RSS_IPV6		M_HASHTYPE_HASH(3) /* IPv6 2-tuple */
562 #define	M_HASHTYPE_RSS_TCP_IPV6		M_HASHTYPE_HASH(4) /* TCPv6 4-tuple */
563 #define	M_HASHTYPE_RSS_IPV6_EX		M_HASHTYPE_HASH(5) /* IPv6 2-tuple +
564 							    * ext hdrs */
565 #define	M_HASHTYPE_RSS_TCP_IPV6_EX	M_HASHTYPE_HASH(6) /* TCPv6 4-tuple +
566 							    * ext hdrs */
567 #define	M_HASHTYPE_RSS_UDP_IPV4		M_HASHTYPE_HASH(7) /* IPv4 UDP 4-tuple*/
568 #define	M_HASHTYPE_RSS_UDP_IPV6		M_HASHTYPE_HASH(9) /* IPv6 UDP 4-tuple*/
569 #define	M_HASHTYPE_RSS_UDP_IPV6_EX	M_HASHTYPE_HASH(10)/* IPv6 UDP 4-tuple +
570 							    * ext hdrs */
571 
572 #define	M_HASHTYPE_OPAQUE		0x3f	/* ordering, not affinity */
573 #define	M_HASHTYPE_OPAQUE_HASH		M_HASHTYPE_HASH(M_HASHTYPE_OPAQUE)
574 						/* ordering+hash, not affinity*/
575 
576 #define	M_HASHTYPE_CLEAR(m)	((m)->m_pkthdr.rsstype = 0)
577 #define	M_HASHTYPE_GET(m)	((m)->m_pkthdr.rsstype & ~M_HASHTYPE_INNER)
578 #define	M_HASHTYPE_SET(m, v)	((m)->m_pkthdr.rsstype = (v))
579 #define	M_HASHTYPE_TEST(m, v)	(M_HASHTYPE_GET(m) == (v))
580 #define	M_HASHTYPE_ISHASH(m)	\
581     (((m)->m_pkthdr.rsstype & M_HASHTYPE_HASHPROP) != 0)
582 #define	M_HASHTYPE_SETINNER(m)	do {			\
583 	(m)->m_pkthdr.rsstype |= M_HASHTYPE_INNER;	\
584     } while (0)
585 
586 /*
587  * External mbuf storage buffer types.
588  */
589 #define	EXT_CLUSTER	1	/* mbuf cluster */
590 #define	EXT_SFBUF	2	/* sendfile(2)'s sf_buf */
591 #define	EXT_JUMBOP	3	/* jumbo cluster page sized */
592 #define	EXT_JUMBO9	4	/* jumbo cluster 9216 bytes */
593 #define	EXT_JUMBO16	5	/* jumbo cluster 16184 bytes */
594 #define	EXT_PACKET	6	/* mbuf+cluster from packet zone */
595 #define	EXT_MBUF	7	/* external mbuf reference */
596 #define	EXT_RXRING	8	/* data in NIC receive ring */
597 #define	EXT_CTL		9	/* buffer from a ctl(4) backend */
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_freemp(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 #define	PACKET_TAG_IPSEC_ACCEL_OUT		32  /* IPSEC accel out */
1390 #define	PACKET_TAG_IPSEC_ACCEL_IN		33  /* IPSEC accel in */
1391 
1392 /* Specific cookies and tags. */
1393 
1394 /* Packet tag routines. */
1395 struct m_tag	*m_tag_alloc(uint32_t, uint16_t, int, int);
1396 void		 m_tag_delete(struct mbuf *, struct m_tag *);
1397 void		 m_tag_delete_chain(struct mbuf *, struct m_tag *);
1398 void		 m_tag_free_default(struct m_tag *);
1399 struct m_tag	*m_tag_locate(struct mbuf *, uint32_t, uint16_t,
1400     struct m_tag *);
1401 struct m_tag	*m_tag_copy(struct m_tag *, int);
1402 int		 m_tag_copy_chain(struct mbuf *, const struct mbuf *, int);
1403 void		 m_tag_delete_nonpersistent(struct mbuf *);
1404 
1405 /*
1406  * Initialize the list of tags associated with an mbuf.
1407  */
1408 static __inline void
1409 m_tag_init(struct mbuf *m)
1410 {
1411 
1412 	SLIST_INIT(&m->m_pkthdr.tags);
1413 }
1414 
1415 /*
1416  * Set up the contents of a tag.  Note that this does not fill in the free
1417  * method; the caller is expected to do that.
1418  *
1419  * XXX probably should be called m_tag_init, but that was already taken.
1420  */
1421 static __inline void
1422 m_tag_setup(struct m_tag *t, uint32_t cookie, uint16_t type, int len)
1423 {
1424 
1425 	t->m_tag_id = type;
1426 	t->m_tag_len = len;
1427 	t->m_tag_cookie = cookie;
1428 }
1429 
1430 /*
1431  * Reclaim resources associated with a tag.
1432  */
1433 static __inline void
1434 m_tag_free(struct m_tag *t)
1435 {
1436 
1437 	(*t->m_tag_free)(t);
1438 }
1439 
1440 /*
1441  * Return the first tag associated with an mbuf.
1442  */
1443 static __inline struct m_tag *
1444 m_tag_first(struct mbuf *m)
1445 {
1446 
1447 	return (SLIST_FIRST(&m->m_pkthdr.tags));
1448 }
1449 
1450 /*
1451  * Return the next tag in the list of tags associated with an mbuf.
1452  */
1453 static __inline struct m_tag *
1454 m_tag_next(struct mbuf *m __unused, struct m_tag *t)
1455 {
1456 
1457 	return (SLIST_NEXT(t, m_tag_link));
1458 }
1459 
1460 /*
1461  * Prepend a tag to the list of tags associated with an mbuf.
1462  */
1463 static __inline void
1464 m_tag_prepend(struct mbuf *m, struct m_tag *t)
1465 {
1466 
1467 	SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link);
1468 }
1469 
1470 /*
1471  * Unlink a tag from the list of tags associated with an mbuf.
1472  */
1473 static __inline void
1474 m_tag_unlink(struct mbuf *m, struct m_tag *t)
1475 {
1476 
1477 	SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link);
1478 }
1479 
1480 /* These are for OpenBSD compatibility. */
1481 #define	MTAG_ABI_COMPAT		0		/* compatibility ABI */
1482 
1483 static __inline struct m_tag *
1484 m_tag_get(uint16_t type, int length, int wait)
1485 {
1486 	return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait));
1487 }
1488 
1489 static __inline struct m_tag *
1490 m_tag_find(struct mbuf *m, uint16_t type, struct m_tag *start)
1491 {
1492 	return (SLIST_EMPTY(&m->m_pkthdr.tags) ? (struct m_tag *)NULL :
1493 	    m_tag_locate(m, MTAG_ABI_COMPAT, type, start));
1494 }
1495 
1496 static inline struct m_snd_tag *
1497 m_snd_tag_ref(struct m_snd_tag *mst)
1498 {
1499 
1500 	refcount_acquire(&mst->refcount);
1501 	return (mst);
1502 }
1503 
1504 static inline void
1505 m_snd_tag_rele(struct m_snd_tag *mst)
1506 {
1507 
1508 	if (refcount_release(&mst->refcount))
1509 		m_snd_tag_destroy(mst);
1510 }
1511 
1512 static __inline struct mbuf *
1513 m_free(struct mbuf *m)
1514 {
1515 	struct mbuf *n = m->m_next;
1516 
1517 	MBUF_PROBE1(m__free, m);
1518 	if ((m->m_flags & (M_PKTHDR|M_NOFREE)) == (M_PKTHDR|M_NOFREE))
1519 		m_tag_delete_chain(m, NULL);
1520 	if (m->m_flags & M_PKTHDR && m->m_pkthdr.csum_flags & CSUM_SND_TAG)
1521 		m_snd_tag_rele(m->m_pkthdr.snd_tag);
1522 	if (m->m_flags & M_EXTPG)
1523 		mb_free_extpg(m);
1524 	else if (m->m_flags & M_EXT)
1525 		mb_free_ext(m);
1526 	else if ((m->m_flags & M_NOFREE) == 0)
1527 		uma_zfree(zone_mbuf, m);
1528 	return (n);
1529 }
1530 
1531 static __inline int
1532 rt_m_getfib(struct mbuf *m)
1533 {
1534 	KASSERT(m->m_flags & M_PKTHDR , ("Attempt to get FIB from non header mbuf."));
1535 	return (m->m_pkthdr.fibnum);
1536 }
1537 
1538 #define M_GETFIB(_m)   rt_m_getfib(_m)
1539 
1540 #define M_SETFIB(_m, _fib) do {						\
1541         KASSERT((_m)->m_flags & M_PKTHDR, ("Attempt to set FIB on non header mbuf."));	\
1542 	((_m)->m_pkthdr.fibnum) = (_fib);				\
1543 } while (0)
1544 
1545 /* flags passed as first argument for "m_xxx_tcpip_hash()" */
1546 #define	MBUF_HASHFLAG_L2	(1 << 2)
1547 #define	MBUF_HASHFLAG_L3	(1 << 3)
1548 #define	MBUF_HASHFLAG_L4	(1 << 4)
1549 
1550 /* mbuf hashing helper routines */
1551 uint32_t	m_ether_tcpip_hash_init(void);
1552 uint32_t	m_ether_tcpip_hash(const uint32_t, const struct mbuf *, uint32_t);
1553 uint32_t	m_infiniband_tcpip_hash_init(void);
1554 uint32_t	m_infiniband_tcpip_hash(const uint32_t, const struct mbuf *, uint32_t);
1555 
1556 #ifdef MBUF_PROFILING
1557  void m_profile(struct mbuf *m);
1558  #define M_PROFILE(m) m_profile(m)
1559 #else
1560  #define M_PROFILE(m)
1561 #endif
1562 
1563 /*
1564  * Structure describing a packet queue: mbufs linked by m_stailqpkt.
1565  * Does accounting of number of packets and has a cap.
1566  */
1567 struct mbufq {
1568 	STAILQ_HEAD(, mbuf)	mq_head;
1569 	int			mq_len;
1570 	int			mq_maxlen;
1571 };
1572 
1573 static inline void
1574 mbufq_init(struct mbufq *mq, int maxlen)
1575 {
1576 
1577 	STAILQ_INIT(&mq->mq_head);
1578 	mq->mq_maxlen = maxlen;
1579 	mq->mq_len = 0;
1580 }
1581 
1582 static inline struct mbuf *
1583 mbufq_flush(struct mbufq *mq)
1584 {
1585 	struct mbuf *m;
1586 
1587 	m = STAILQ_FIRST(&mq->mq_head);
1588 	STAILQ_INIT(&mq->mq_head);
1589 	mq->mq_len = 0;
1590 	return (m);
1591 }
1592 
1593 static inline void
1594 mbufq_drain(struct mbufq *mq)
1595 {
1596 	struct mbuf *m, *n;
1597 
1598 	n = mbufq_flush(mq);
1599 	while ((m = n) != NULL) {
1600 		n = STAILQ_NEXT(m, m_stailqpkt);
1601 		m_freem(m);
1602 	}
1603 }
1604 
1605 static inline struct mbuf *
1606 mbufq_first(const struct mbufq *mq)
1607 {
1608 
1609 	return (STAILQ_FIRST(&mq->mq_head));
1610 }
1611 
1612 static inline struct mbuf *
1613 mbufq_last(const struct mbufq *mq)
1614 {
1615 
1616 	return (STAILQ_LAST(&mq->mq_head, mbuf, m_stailqpkt));
1617 }
1618 
1619 static inline bool
1620 mbufq_empty(const struct mbufq *mq)
1621 {
1622 	return (mq->mq_len == 0);
1623 }
1624 
1625 static inline int
1626 mbufq_full(const struct mbufq *mq)
1627 {
1628 
1629 	return (mq->mq_maxlen > 0 && mq->mq_len >= mq->mq_maxlen);
1630 }
1631 
1632 static inline int
1633 mbufq_len(const struct mbufq *mq)
1634 {
1635 
1636 	return (mq->mq_len);
1637 }
1638 
1639 static inline int
1640 mbufq_enqueue(struct mbufq *mq, struct mbuf *m)
1641 {
1642 
1643 	if (mbufq_full(mq))
1644 		return (ENOBUFS);
1645 	STAILQ_INSERT_TAIL(&mq->mq_head, m, m_stailqpkt);
1646 	mq->mq_len++;
1647 	return (0);
1648 }
1649 
1650 static inline struct mbuf *
1651 mbufq_dequeue(struct mbufq *mq)
1652 {
1653 	struct mbuf *m;
1654 
1655 	m = STAILQ_FIRST(&mq->mq_head);
1656 	if (m) {
1657 		STAILQ_REMOVE_HEAD(&mq->mq_head, m_stailqpkt);
1658 		m->m_nextpkt = NULL;
1659 		mq->mq_len--;
1660 	}
1661 	return (m);
1662 }
1663 
1664 static inline void
1665 mbufq_prepend(struct mbufq *mq, struct mbuf *m)
1666 {
1667 
1668 	STAILQ_INSERT_HEAD(&mq->mq_head, m, m_stailqpkt);
1669 	mq->mq_len++;
1670 }
1671 
1672 /*
1673  * Note: this doesn't enforce the maximum list size for dst.
1674  */
1675 static inline void
1676 mbufq_concat(struct mbufq *mq_dst, struct mbufq *mq_src)
1677 {
1678 
1679 	mq_dst->mq_len += mq_src->mq_len;
1680 	STAILQ_CONCAT(&mq_dst->mq_head, &mq_src->mq_head);
1681 	mq_src->mq_len = 0;
1682 }
1683 
1684 /*
1685  * Structure describing a chain of mbufs linked by m_stailq, also tracking
1686  * the pointer to the last.  Also does accounting of data length and memory
1687  * usage.
1688  * To be used as an argument to mbuf chain allocation and manipulation KPIs,
1689  * and can be allocated on the stack of a caller.  Kernel facilities may use
1690  * it internally as a most simple implementation of a stream data buffer.
1691  */
1692 struct mchain {
1693 	STAILQ_HEAD(, mbuf) mc_q;
1694 	u_int mc_len;
1695 	u_int mc_mlen;
1696 };
1697 
1698 #define	MCHAIN_INITIALIZER(mc)	\
1699 	(struct mchain){ .mc_q = STAILQ_HEAD_INITIALIZER((mc)->mc_q) }
1700 
1701 static inline struct mbuf *
1702 mc_first(struct mchain *mc)
1703 {
1704 	return (STAILQ_FIRST(&mc->mc_q));
1705 }
1706 
1707 static inline struct mbuf *
1708 mc_last(struct mchain *mc)
1709 {
1710 	return (STAILQ_LAST(&mc->mc_q, mbuf, m_stailq));
1711 }
1712 
1713 static inline bool
1714 mc_empty(struct mchain *mc)
1715 {
1716 	return (STAILQ_EMPTY(&mc->mc_q));
1717 }
1718 
1719 /* Account addition of m to mc. */
1720 static inline void
1721 mc_inc(struct mchain *mc, struct mbuf *m)
1722 {
1723 	mc->mc_len += m->m_len;
1724 	mc->mc_mlen += MSIZE;
1725 	if (m->m_flags & M_EXT)
1726 		mc->mc_mlen += m->m_ext.ext_size;
1727 }
1728 
1729 /* Account removal of m from mc. */
1730 static inline void
1731 mc_dec(struct mchain *mc, struct mbuf *m)
1732 {
1733 	MPASS(mc->mc_len >= m->m_len);
1734 	mc->mc_len -= m->m_len;
1735 	MPASS(mc->mc_mlen >= MSIZE);
1736 	mc->mc_mlen -= MSIZE;
1737 	if (m->m_flags & M_EXT) {
1738 		MPASS(mc->mc_mlen >= m->m_ext.ext_size);
1739 		mc->mc_mlen -= m->m_ext.ext_size;
1740 	}
1741 }
1742 
1743 /*
1744  * Get mchain from a classic mbuf chain linked by m_next.  Two hacks here:
1745  * we use the fact that m_next is alias to m_stailq, we use internal queue(3)
1746  * fields.
1747  */
1748 static inline void
1749 mc_init_m(struct mchain *mc, struct mbuf *m)
1750 {
1751 	struct mbuf *last;
1752 
1753 	STAILQ_FIRST(&mc->mc_q) = m;
1754 	mc->mc_len = mc->mc_mlen = 0;
1755 	STAILQ_FOREACH(m, &mc->mc_q, m_stailq) {
1756 		mc_inc(mc, m);
1757 		last = m;
1758 	}
1759 	mc->mc_q.stqh_last = &STAILQ_NEXT(last, m_stailq);
1760 }
1761 
1762 static inline void
1763 mc_freem(struct mchain *mc)
1764 {
1765 	if (!mc_empty(mc))
1766 		m_freem(mc_first(mc));
1767 }
1768 
1769 static inline void
1770 mc_prepend(struct mchain *mc, struct mbuf *m)
1771 {
1772 	STAILQ_INSERT_HEAD(&mc->mc_q, m, m_stailq);
1773 	mc_inc(mc, m);
1774 }
1775 
1776 static inline void
1777 mc_append(struct mchain *mc, struct mbuf *m)
1778 {
1779 	STAILQ_INSERT_TAIL(&mc->mc_q, m, m_stailq);
1780 	mc_inc(mc, m);
1781 }
1782 
1783 static inline void
1784 mc_concat(struct mchain *head, struct mchain *tail)
1785 {
1786 	STAILQ_CONCAT(&head->mc_q, &tail->mc_q);
1787 	head->mc_len += tail->mc_len;
1788 	head->mc_mlen += tail->mc_mlen;
1789 	tail->mc_len = tail->mc_mlen = 0;
1790 }
1791 
1792 /*
1793  * Note: STAILQ_REMOVE() is expensive. mc_remove_after() needs to be provided
1794  * as long as there consumers that would benefit from it.
1795  */
1796 static inline void
1797 mc_remove(struct mchain *mc, struct mbuf *m)
1798 {
1799 	STAILQ_REMOVE(&mc->mc_q, m, mbuf, m_stailq);
1800 	mc_dec(mc, m);
1801 }
1802 
1803 int mc_get(struct mchain *, u_int, int, short, int);
1804 int mc_split(struct mchain *, struct mchain *, u_int, int);
1805 int mc_uiotomc(struct mchain *, struct uio *, u_int, u_int, int, int);
1806 
1807 #ifdef _SYS_TIMESPEC_H_
1808 static inline void
1809 mbuf_tstmp2timespec(struct mbuf *m, struct timespec *ts)
1810 {
1811 
1812 	KASSERT((m->m_flags & M_PKTHDR) != 0, ("mbuf %p no M_PKTHDR", m));
1813 	KASSERT((m->m_flags & (M_TSTMP|M_TSTMP_LRO)) != 0,
1814 	    ("mbuf %p no M_TSTMP or M_TSTMP_LRO", m));
1815 	ts->tv_sec = m->m_pkthdr.rcv_tstmp / 1000000000;
1816 	ts->tv_nsec = m->m_pkthdr.rcv_tstmp % 1000000000;
1817 }
1818 #endif
1819 
1820 static inline void
1821 mbuf_tstmp2timeval(struct mbuf *m, struct timeval *tv)
1822 {
1823 
1824 	KASSERT((m->m_flags & M_PKTHDR) != 0, ("mbuf %p no M_PKTHDR", m));
1825 	KASSERT((m->m_flags & (M_TSTMP|M_TSTMP_LRO)) != 0,
1826 	    ("mbuf %p no M_TSTMP or M_TSTMP_LRO", m));
1827 	tv->tv_sec = m->m_pkthdr.rcv_tstmp / 1000000000;
1828 	tv->tv_usec = (m->m_pkthdr.rcv_tstmp % 1000000000) / 1000;
1829 }
1830 
1831 #ifdef DEBUGNET
1832 /* Invoked from the debugnet client code. */
1833 void	debugnet_mbuf_drain(void);
1834 void	debugnet_mbuf_start(void);
1835 void	debugnet_mbuf_finish(void);
1836 void	debugnet_mbuf_reinit(int nmbuf, int nclust, int clsize);
1837 #endif
1838 
1839 static inline bool
1840 mbuf_has_tls_session(struct mbuf *m)
1841 {
1842 
1843 	if (m->m_flags & M_EXTPG) {
1844 		if (m->m_epg_tls != NULL) {
1845 			return (true);
1846 		}
1847 	}
1848 	return (false);
1849 }
1850 
1851 #endif /* _KERNEL */
1852 #endif /* !_SYS_MBUF_H_ */
1853