/* * Copyright (c) 2004 The DragonFly Project. All rights reserved. * * Copyright (c) 1982, 1986, 1988, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)mbuf.h 8.5 (Berkeley) 2/19/95 * $FreeBSD: src/sys/sys/mbuf.h,v 1.44.2.17 2003/04/15 06:15:02 silby Exp $ * $DragonFly: src/sys/sys/mbuf.h,v 1.36 2006/06/14 04:39:05 y0netan1 Exp $ */ #ifndef _SYS_MBUF_H_ #define _SYS_MBUF_H_ #if defined(_KERNEL) || defined(_KERNEL_STRUCTURES) #ifndef _SYS_TYPES_H_ #include #endif #ifndef _SYS_PARAM_H_ #include #endif #ifndef _SYS_QUEUE_H_ #include #endif #ifndef _NET_NETISR_H_ #include #endif /* * Mbufs are of a single size, MSIZE (machine/param.h), which * includes overhead. An mbuf may add a single "mbuf cluster" of size * MCLBYTES (also in machine/param.h), which has no additional overhead * and is used instead of the internal data area; this is done when * at least MINCLSIZE of data must be stored. */ #define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */ #define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */ #define MINCLSIZE (MHLEN + 1) /* smallest amount to put in cluster */ #define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */ /* * Macros for type conversion: * mtod(m, t) -- Convert mbuf pointer to data pointer of correct type. * mtocl(x) - convert pointer within cluster to cluster index # * cltom(x) - convert cluster # to ptr to beginning of cluster */ #define mtod(m, t) ((t)((m)->m_data)) /* * Header present at the beginning of every mbuf. */ struct m_hdr { struct mbuf *mh_next; /* next buffer in chain */ struct mbuf *mh_nextpkt; /* next chain in queue/record */ caddr_t mh_data; /* location of data */ int mh_len; /* amount of data in this mbuf */ short mh_type; /* type of data in this mbuf */ short mh_flags; /* flags; see below */ struct netmsg_packet mh_netmsg; /* hardware->proto stack msg */ }; /* * Packet tag structure (see below for details). */ struct m_tag { SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */ u_int16_t m_tag_id; /* Tag ID */ u_int16_t m_tag_len; /* Length of data */ u_int32_t m_tag_cookie; /* ABI/Module ID */ }; SLIST_HEAD(packet_tags, m_tag); /* * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set. * * Be careful: The fields have been carefully ordered to avoid hidden padding. * Keep this in mind, when adding or removing fields! */ struct pkthdr { struct ifnet *rcvif; /* rcv interface */ int len; /* total packet length */ struct packet_tags tags; /* list of packet tags */ /* variables for ip and tcp reassembly */ void *header; /* pointer to packet header */ /* variables for hardware checksum */ int csum_flags; /* flags regarding checksum */ int csum_data; /* data field used by csum routines */ /* firewall flags */ uint32_t fw_flags; /* flags for PF */ /* variables for PF processing */ uint16_t pf_tag; /* PF tag id */ uint8_t pf_routed; /* PF routing counter */ /* variables for ALTQ processing */ uint8_t ecn_af; /* address family for ECN */ uint32_t altq_qid; /* queue id */ }; /* * Description of external storage mapped into mbuf; valid only if M_EXT is set. */ struct m_ext { caddr_t ext_buf; /* start of buffer */ void (*ext_free)(void *); u_int ext_size; /* size of buffer, for ext_free */ void (*ext_ref)(void *); void *ext_arg; }; /* * The core of the mbuf object along with some shortcut defines for * practical purposes. */ struct mbuf { struct m_hdr m_hdr; union { struct { struct pkthdr MH_pkthdr; /* M_PKTHDR set */ union { struct m_ext MH_ext; /* M_EXT set */ char MH_databuf[MHLEN]; } MH_dat; } MH; char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */ } M_dat; }; #define m_next m_hdr.mh_next #define m_len m_hdr.mh_len #define m_data m_hdr.mh_data #define m_type m_hdr.mh_type #define m_flags m_hdr.mh_flags #define m_nextpkt m_hdr.mh_nextpkt #define m_pkthdr M_dat.MH.MH_pkthdr #define m_ext M_dat.MH.MH_dat.MH_ext #define m_pktdat M_dat.MH.MH_dat.MH_databuf #define m_dat M_dat.M_databuf /* * Code that uses m_act should be converted to use m_nextpkt * instead; m_act is historical and deprecated. */ #define m_act m_nextpkt /* * mbuf flags. */ #define M_EXT 0x0001 /* has associated external storage */ #define M_PKTHDR 0x0002 /* start of record */ #define M_EOR 0x0004 /* end of record */ #define M_PROTO1 0x0008 /* protocol-specific */ #define M_PROTO2 0x0010 /* protocol-specific */ #define M_PROTO3 0x0020 /* protocol-specific */ #define M_PROTO4 0x0040 /* protocol-specific */ #define M_PROTO5 0x0080 /* protocol-specific */ /* * mbuf pkthdr flags (also stored in m_flags). */ #define M_BCAST 0x0100 /* send/received as link-level broadcast */ #define M_MCAST 0x0200 /* send/received as link-level multicast */ #define M_FRAG 0x0400 /* packet is a fragment of a larger packet */ #define M_FIRSTFRAG 0x0800 /* packet is first fragment */ #define M_LASTFRAG 0x1000 /* packet is last fragment */ #define M_CLCACHE 0x2000 /* mbuf allocated from the cluster cache */ #define M_EXT_CLUSTER 0x4000 /* standard cluster else special */ #define M_PHCACHE 0x8000 /* mbuf allocated from the pkt header cache */ #define M_NOTIFICATION 0x10000 /* notification event */ /* * Flags copied when copying m_pkthdr. */ #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_PROTO1|M_PROTO1|M_PROTO2|M_PROTO3 | \ M_PROTO4|M_PROTO5|M_BCAST|M_MCAST|M_FRAG | \ M_FIRSTFRAG|M_LASTFRAG) /* * Flags indicating hw checksum support and sw checksum requirements. */ #define CSUM_IP 0x0001 /* will csum IP */ #define CSUM_TCP 0x0002 /* will csum TCP */ #define CSUM_UDP 0x0004 /* will csum UDP */ #define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */ #define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */ #define CSUM_IP_CHECKED 0x0100 /* did csum IP */ #define CSUM_IP_VALID 0x0200 /* ... the csum is valid */ #define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */ #define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */ #define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP) #define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */ /* * Flags indicating PF processing status */ #define PF_MBUF_GENERATED 0x00000001 #define PF_MBUF_TAGGED 0x00000002 /* pf_tag field is valid */ #define PF_MBUF_ROUTED 0x00000004 /* pf_routed field is valid */ #define PF_MBUF_TRANSLATE_LOCALHOST \ 0x00000008 #define PF_MBUF_FRAGCACHE 0x00000010 #define ALTQ_MBUF_TAGGED 0x00000020 /* altq_qid is valid */ #define IPFW_MBUF_SKIP_FIREWALL 0x00000040 /* * mbuf types. */ #define MT_FREE 0 /* should be on free list */ #define MT_DATA 1 /* dynamic (data) allocation */ #define MT_HEADER 2 /* packet header */ #define MT_SONAME 3 /* socket name */ #define MT_TAG 4 /* volatile metadata associated to pkts */ #define MT_CONTROL 5 /* extra-data protocol message */ #define MT_OOBDATA 6 /* expedited data */ #define MT_NTYPES 7 /* number of mbuf types for mbtypes[] */ /* * General mbuf allocator statistics structure. */ struct mbstat { u_long m_mbufs; /* mbufs obtained from page pool */ u_long m_clusters; /* clusters obtained from page pool */ u_long m_spare; /* spare field */ u_long m_clfree; /* free clusters */ u_long m_drops; /* times failed to find space */ u_long m_wait; /* times waited for space */ u_long m_drain; /* times drained protocols for space */ u_long m_mcfail; /* times m_copym failed */ u_long m_mpfail; /* times m_pullup failed */ u_long m_msize; /* length of an mbuf */ u_long m_mclbytes; /* length of an mbuf cluster */ u_long m_minclsize; /* min length of data to allocate a cluster */ u_long m_mlen; /* length of data in an mbuf */ u_long m_mhlen; /* length of data in a header mbuf */ }; /* * Flags specifying how an allocation should be made. */ #define MB_DONTWAIT 0x4 #define MB_TRYWAIT 0x8 #define MB_WAIT MB_TRYWAIT /* * Mbuf to Malloc Flag Conversion. */ #define MBTOM(how) ((how) & MB_TRYWAIT ? M_WAITOK : M_NOWAIT) /* * These are identifying numbers passed to the m_mballoc_wait function, * allowing us to determine whether the call came from an MGETHDR or * an MGET. */ #define MGETHDR_C 1 #define MGET_C 2 /* * mbuf allocation/deallocation macros (YYY deprecated, too big): * * MGET(struct mbuf *m, int how, int type) * allocates an mbuf and initializes it to contain internal data. * * MGETHDR(struct mbuf *m, int how, int type) * allocates an mbuf and initializes it to contain a packet header * and internal data. */ #define MGET(m, how, type) do { \ (m) = m_get((how), (type)); \ } while (0) #define MGETHDR(m, how, type) do { \ (m) = m_gethdr((how), (type)); \ } while (0) /* * MCLGET adds such clusters to a normal mbuf. The flag M_EXT is set upon * success. * Deprecated. Use m_getcl() or m_getl() instead. */ #define MCLGET(m, how) do { \ m_mclget((m), (how)); \ } while (0) /* * NB: M_COPY_PKTHDR is deprecated; use either M_MOVE_PKTHDR * or m_dup_pkthdr. */ /* * Move mbuf pkthdr from "from" to "to". * from should have M_PKTHDR set, and to must be empty. * from no longer has a pkthdr after this operation. */ #define M_MOVE_PKTHDR(_to, _from) m_move_pkthdr((_to), (_from)) /* * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place * an object of the specified size at the end of the mbuf, longword aligned. */ #define M_ALIGN(m, len) do { \ (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \ } while (0) /* * As above, for mbufs allocated with m_gethdr/MGETHDR * or initialized by M_COPY_PKTHDR. */ #define MH_ALIGN(m, len) do { \ (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \ } while (0) /* * Check if we can write to an mbuf. */ #define M_EXT_WRITABLE(m) (m_sharecount(m) == 1) #define M_WRITABLE(m) (!((m)->m_flags & M_EXT) || M_EXT_WRITABLE(m)) /* * Check if the supplied mbuf has a packet header, or else panic. */ #define M_ASSERTPKTHDR(m) \ KASSERT(m != NULL && m->m_flags & M_PKTHDR, \ ("%s: invalid mbuf or no mbuf packet header!", __func__)) /* * Compute the amount of space available before the current start of data. * The M_EXT_WRITABLE() is a temporary, conservative safety measure: the burden * of checking writability of the mbuf data area rests solely with the caller. */ #define M_LEADINGSPACE(m) \ ((m)->m_flags & M_EXT ? \ (M_EXT_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \ (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \ (m)->m_data - (m)->m_dat) /* * Compute the amount of space available after the end of data in an mbuf. * The M_WRITABLE() is a temporary, conservative safety measure: the burden * of checking writability of the mbuf data area rests solely with the caller. */ #define M_TRAILINGSPACE(m) \ ((m)->m_flags & M_EXT ? \ (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \ - ((m)->m_data + (m)->m_len) : 0) : \ &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len)) /* * Arrange to prepend space of size plen to mbuf m. * If a new mbuf must be allocated, how specifies whether to wait. * If how is MB_DONTWAIT and allocation fails, the original mbuf chain * is freed and m is set to NULL. */ #define M_PREPEND(m, plen, how) do { \ struct mbuf **_mmp = &(m); \ struct mbuf *_mm = *_mmp; \ int _mplen = (plen); \ int __mhow = (how); \ \ if (M_LEADINGSPACE(_mm) >= _mplen) { \ _mm->m_data -= _mplen; \ _mm->m_len += _mplen; \ } else \ _mm = m_prepend(_mm, _mplen, __mhow); \ if (_mm != NULL && _mm->m_flags & M_PKTHDR) \ _mm->m_pkthdr.len += _mplen; \ *_mmp = _mm; \ } while (0) /* Length to m_copy to copy all. */ #define M_COPYALL 1000000000 /* Compatibility with 4.3 */ #define m_copy(m, o, l) m_copym((m), (o), (l), MB_DONTWAIT) #ifdef _KERNEL extern u_int m_clalloc_wid; /* mbuf cluster wait count */ extern u_int m_mballoc_wid; /* mbuf wait count */ extern int max_linkhdr; /* largest link-level header */ extern int max_protohdr; /* largest protocol header */ extern int max_hdr; /* largest link+protocol header */ extern int max_datalen; /* MHLEN - max_hdr */ extern struct mbstat mbstat; extern int mbuf_wait; /* mbuf sleep time */ extern int nmbclusters; extern int nmbufs; struct uio; void m_adj(struct mbuf *, int); void m_cat(struct mbuf *, struct mbuf *); u_int m_countm(struct mbuf *m, struct mbuf **lastm, u_int *mbcnt); void m_copyback(struct mbuf *, int, int, caddr_t); void m_copydata(const struct mbuf *, int, int, caddr_t); struct mbuf *m_copym(const struct mbuf *, int, int, int); struct mbuf *m_copypacket(struct mbuf *, int); struct mbuf *m_defrag(struct mbuf *, int); struct mbuf *m_defrag_nofree(struct mbuf *, int); struct mbuf *m_devget(char *, int, int, struct ifnet *, void (*copy)(volatile const void *, volatile void *, size_t)); struct mbuf *m_dup(struct mbuf *, int); int m_dup_pkthdr(struct mbuf *, const struct mbuf *, int); struct mbuf *m_free(struct mbuf *); void m_freem(struct mbuf *); struct mbuf *m_get(int, int); struct mbuf *m_getc(int len, int how, int type); struct mbuf *m_getcl(int how, short type, int flags); struct mbuf *m_getclr(int, int); struct mbuf *m_gethdr(int, int); struct mbuf *m_getm(struct mbuf *, int, int, int); struct mbuf *m_last(struct mbuf *m); u_int m_lengthm(struct mbuf *m, struct mbuf **lastm); void m_move_pkthdr(struct mbuf *, struct mbuf *); struct mbuf *m_prepend(struct mbuf *, int, int); void m_print(const struct mbuf *m); struct mbuf *m_pulldown(struct mbuf *, int, int, int *); struct mbuf *m_pullup(struct mbuf *, int); struct mbuf *m_split(struct mbuf *, int, int); struct mbuf *m_uiomove(struct uio *); void m_mclget(struct mbuf *m, int how); int m_sharecount(struct mbuf *m); void m_chtype(struct mbuf *m, int type); /* * Allocate the right type of mbuf for the desired total length. */ static __inline struct mbuf * m_getl(int len, int how, int type, int flags, int *psize) { struct mbuf *m; int size; if (len >= MINCLSIZE) { m = m_getcl(how, type, flags); size = MCLBYTES; } else if (flags & M_PKTHDR) { m = m_gethdr(how, type); size = MHLEN; } else { m = m_get(how, type); size = MLEN; } if (psize != NULL) *psize = size; return (m); } /* * Packets may have annotations attached by affixing a list * of "packet tags" to the pkthdr structure. Packet tags are * dynamically allocated semi-opaque data structures that have * a fixed header (struct m_tag) that specifies the size of the * memory block and a pair that identifies it. * The cookie is a 32-bit unique unsigned value used to identify * a module or ABI. By convention this value is chose as the * date+time that the module is created, expressed as the number of * seconds since the epoch (e.g. using date -u +'%s'). The type value * is an ABI/module-specific value that identifies a particular annotation * and is private to the module. For compatibility with systems * like openbsd that define packet tags w/o an ABI/module cookie, * the value PACKET_ABI_COMPAT is used to implement m_tag_get and * m_tag_find compatibility shim functions and several tag types are * defined below. Users that do not require compatibility should use * a private cookie value so that packet tag-related definitions * can be maintained privately. * * Note that the packet tag returned by m_tag_allocate has the default * memory alignment implemented by malloc. To reference private data * one can use a construct like: * * struct m_tag *mtag = m_tag_allocate(...); * struct foo *p = (struct foo *)(mtag+1); * * if the alignment of struct m_tag is sufficient for referencing members * of struct foo. Otherwise it is necessary to embed struct m_tag within * the private data structure to insure proper alignment; e.g. * * struct foo { * struct m_tag tag; * ... * }; * struct foo *p = (struct foo *) m_tag_allocate(...); * struct m_tag *mtag = &p->tag; */ #define PACKET_TAG_NONE 0 /* Nadda */ /* Packet tag for use with PACKET_ABI_COMPAT */ #define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */ /* struct tdb_indent */ #define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */ /* struct tdb_indent */ #define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */ /* struct tdb_indent, never added */ #define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */ /* struct tdb_indent, never added */ #define PACKET_TAG_IPSEC_PENDING_TDB 5 /* Reminder to do IPsec */ /* struct tdb_indent, never added */ #define PACKET_TAG_ENCAP 6 /* Encap. processing */ /* struct ifnet *, the GIF interface */ #define PACKET_TAG_IPSEC_HISTORY 7 /* IPSEC history */ /* struct ipsec_history */ #define PACKET_TAG_IPV6_INPUT 8 /* IPV6 input processing */ /* struct ip6aux */ #define PACKET_TAG_IPFW_DIVERT 9 /* divert info */ /* uint16_t */ /* * As a temporary and low impact solution to replace the even uglier * approach used so far in some parts of the network stack (which relies * on global variables), packet tag-like annotations are stored in MT_TAG * mbufs (or lookalikes) prepended to the actual mbuf chain. * * m_type = MT_TAG * m_flags = m_tag_id * m_next = next buffer in chain. * * BE VERY CAREFUL not to pass these blocks to the mbuf handling routines. */ #define _m_tag_id m_hdr.mh_flags /* Packet tags used in the FreeBSD network stack */ #define PACKET_TAG_DUMMYNET 15 /* dummynet info */ /* struct dn_pkt as fake mbuf */ #define PACKET_TAG_IPFORWARD 18 /* ipforward info */ /* struct sockaddr_in * as m_data */ /* Packet tag routines */ struct m_tag *m_tag_alloc(u_int32_t, int, int, int); void m_tag_free(struct m_tag *); void m_tag_prepend(struct mbuf *, struct m_tag *); void m_tag_unlink(struct mbuf *, struct m_tag *); void m_tag_delete(struct mbuf *, struct m_tag *); void m_tag_delete_chain(struct mbuf *); struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *); struct m_tag *m_tag_copy(struct m_tag *, int); int m_tag_copy_chain(struct mbuf *, const struct mbuf *, int); void m_tag_init(struct mbuf *); struct m_tag *m_tag_first(struct mbuf *); struct m_tag *m_tag_next(struct mbuf *, struct m_tag *); /* these are for openbsd compatibility */ #define MTAG_ABI_COMPAT 0 /* compatibility ABI */ static __inline void * m_tag_data(struct m_tag *tag) { return ((void *)(tag + 1)); } static __inline struct m_tag * m_tag_get(int type, int length, int wait) { return m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait); } static __inline struct m_tag * m_tag_find(struct mbuf *m, int type, struct m_tag *start) { return m_tag_locate(m, MTAG_ABI_COMPAT, type, start); } #endif /* _KERNEL */ #endif /* _KERNEL || _KERNEL_STRUCTURES */ #endif /* !_SYS_MBUF_H_ */