The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/sys/mbuf.h

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    1 /*-
    2  * Copyright (c) 1982, 1986, 1988, 1993
    3  *      The Regents of the University of California.
    4  * All rights reserved.
    5  *
    6  * Redistribution and use in source and binary forms, with or without
    7  * modification, are permitted provided that the following conditions
    8  * are met:
    9  * 1. Redistributions of source code must retain the above copyright
   10  *    notice, this list of conditions and the following disclaimer.
   11  * 2. Redistributions in binary form must reproduce the above copyright
   12  *    notice, this list of conditions and the following disclaimer in the
   13  *    documentation and/or other materials provided with the distribution.
   14  * 3. Neither the name of the University nor the names of its contributors
   15  *    may be used to endorse or promote products derived from this software
   16  *    without specific prior written permission.
   17  *
   18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   28  * SUCH DAMAGE.
   29  *
   30  *      @(#)mbuf.h      8.5 (Berkeley) 2/19/95
   31  * $FreeBSD: head/sys/sys/mbuf.h 296242 2016-03-01 00:17:14Z glebius $
   32  */
   33 
   34 #ifndef _SYS_MBUF_H_
   35 #define _SYS_MBUF_H_
   36 
   37 /* XXX: These includes suck. Sorry! */
   38 #include <sys/queue.h>
   39 #ifdef _KERNEL
   40 #include <sys/systm.h>
   41 #include <vm/uma.h>
   42 #ifdef WITNESS
   43 #include <sys/lock.h>
   44 #endif
   45 #endif
   46 
   47 /*
   48  * Mbufs are of a single size, MSIZE (sys/param.h), which includes overhead.
   49  * An mbuf may add a single "mbuf cluster" of size MCLBYTES (also in
   50  * sys/param.h), which has no additional overhead and is used instead of the
   51  * internal data area; this is done when at least MINCLSIZE of data must be
   52  * stored.  Additionally, it is possible to allocate a separate buffer
   53  * externally and attach it to the mbuf in a way similar to that of mbuf
   54  * clusters.
   55  *
   56  * NB: These calculation do not take actual compiler-induced alignment and
   57  * padding inside the complete struct mbuf into account.  Appropriate
   58  * attention is required when changing members of struct mbuf.
   59  *
   60  * MLEN is data length in a normal mbuf.
   61  * MHLEN is data length in an mbuf with pktheader.
   62  * MINCLSIZE is a smallest amount of data that should be put into cluster.
   63  *
   64  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
   65  * they are sensible.
   66  */
   67 struct mbuf;
   68 #define MHSIZE          offsetof(struct mbuf, m_dat)
   69 #define MPKTHSIZE       offsetof(struct mbuf, m_pktdat)
   70 #define MLEN            ((int)(MSIZE - MHSIZE))
   71 #define MHLEN           ((int)(MSIZE - MPKTHSIZE))
   72 #define MINCLSIZE       (MHLEN + 1)
   73 
   74 #ifdef _KERNEL
   75 /*-
   76  * Macro for type conversion: convert mbuf pointer to data pointer of correct
   77  * type:
   78  *
   79  * mtod(m, t)   -- Convert mbuf pointer to data pointer of correct type.
   80  * mtodo(m, o) -- Same as above but with offset 'o' into data.
   81  */
   82 #define mtod(m, t)      ((t)((m)->m_data))
   83 #define mtodo(m, o)     ((void *)(((m)->m_data) + (o)))
   84 
   85 /*
   86  * Argument structure passed to UMA routines during mbuf and packet
   87  * allocations.
   88  */
   89 struct mb_args {
   90         int     flags;  /* Flags for mbuf being allocated */
   91         short   type;   /* Type of mbuf being allocated */
   92 };
   93 #endif /* _KERNEL */
   94 
   95 /*
   96  * Packet tag structure (see below for details).
   97  */
   98 struct m_tag {
   99         SLIST_ENTRY(m_tag)      m_tag_link;     /* List of packet tags */
  100         u_int16_t               m_tag_id;       /* Tag ID */
  101         u_int16_t               m_tag_len;      /* Length of data */
  102         u_int32_t               m_tag_cookie;   /* ABI/Module ID */
  103         void                    (*m_tag_free)(struct m_tag *);
  104 };
  105 
  106 /*
  107  * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set.
  108  * Size ILP32: 48
  109  *       LP64: 56
  110  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
  111  * they are correct.
  112  */
  113 struct pkthdr {
  114         struct ifnet    *rcvif;         /* rcv interface */
  115         SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */
  116         int32_t          len;           /* total packet length */
  117 
  118         /* Layer crossing persistent information. */
  119         uint32_t         flowid;        /* packet's 4-tuple system */
  120         uint64_t         csum_flags;    /* checksum and offload features */
  121         uint16_t         fibnum;        /* this packet should use this fib */
  122         uint8_t          cosqos;        /* class/quality of service */
  123         uint8_t          rsstype;       /* hash type */
  124         uint8_t          l2hlen;        /* layer 2 header length */
  125         uint8_t          l3hlen;        /* layer 3 header length */
  126         uint8_t          l4hlen;        /* layer 4 header length */
  127         uint8_t          l5hlen;        /* layer 5 header length */
  128         union {
  129                 uint8_t  eight[8];
  130                 uint16_t sixteen[4];
  131                 uint32_t thirtytwo[2];
  132                 uint64_t sixtyfour[1];
  133                 uintptr_t unintptr[1];
  134                 void    *ptr;
  135         } PH_per;
  136 
  137         /* Layer specific non-persistent local storage for reassembly, etc. */
  138         union {
  139                 uint8_t  eight[8];
  140                 uint16_t sixteen[4];
  141                 uint32_t thirtytwo[2];
  142                 uint64_t sixtyfour[1];
  143                 uintptr_t unintptr[1];
  144                 void    *ptr;
  145         } PH_loc;
  146 };
  147 #define ether_vtag      PH_per.sixteen[0]
  148 #define PH_vt           PH_per
  149 #define vt_nrecs        sixteen[0]
  150 #define tso_segsz       PH_per.sixteen[1]
  151 #define csum_phsum      PH_per.sixteen[2]
  152 #define csum_data       PH_per.thirtytwo[1]
  153 
  154 /*
  155  * Description of external storage mapped into mbuf; valid only if M_EXT is
  156  * set.
  157  * Size ILP32: 28
  158  *       LP64: 48
  159  * Compile-time assertions in uipc_mbuf.c test these values to ensure that
  160  * they are correct.
  161  */
  162 struct m_ext {
  163         union {
  164                 volatile u_int   ext_count;     /* value of ref count info */
  165                 volatile u_int  *ext_cnt;       /* pointer to ref count info */
  166         };
  167         caddr_t          ext_buf;       /* start of buffer */
  168         uint32_t         ext_size;      /* size of buffer, for ext_free */
  169         uint32_t         ext_type:8,    /* type of external storage */
  170                          ext_flags:24;  /* external storage mbuf flags */
  171         void            (*ext_free)     /* free routine if not the usual */
  172                             (struct mbuf *, void *, void *);
  173         void            *ext_arg1;      /* optional argument pointer */
  174         void            *ext_arg2;      /* optional argument pointer */
  175 };
  176 
  177 /*
  178  * The core of the mbuf object along with some shortcut defines for practical
  179  * purposes.
  180  */
  181 struct mbuf {
  182         /*
  183          * Header present at the beginning of every mbuf.
  184          * Size ILP32: 24
  185          *      LP64: 32
  186          * Compile-time assertions in uipc_mbuf.c test these values to ensure
  187          * that they are correct.
  188          */
  189         union { /* next buffer in chain */
  190                 struct mbuf             *m_next;
  191                 SLIST_ENTRY(mbuf)       m_slist;
  192                 STAILQ_ENTRY(mbuf)      m_stailq;
  193         };
  194         union { /* next chain in queue/record */
  195                 struct mbuf             *m_nextpkt;
  196                 SLIST_ENTRY(mbuf)       m_slistpkt;
  197                 STAILQ_ENTRY(mbuf)      m_stailqpkt;
  198         };
  199         caddr_t          m_data;        /* location of data */
  200         int32_t          m_len;         /* amount of data in this mbuf */
  201         uint32_t         m_type:8,      /* type of data in this mbuf */
  202                          m_flags:24;    /* flags; see below */
  203 #if !defined(__LP64__)
  204         uint32_t         m_pad;         /* pad for 64bit alignment */
  205 #endif
  206 
  207         /*
  208          * A set of optional headers (packet header, external storage header)
  209          * and internal data storage.  Historically, these arrays were sized
  210          * to MHLEN (space left after a packet header) and MLEN (space left
  211          * after only a regular mbuf header); they are now variable size in
  212          * order to support future work on variable-size mbufs.
  213          */
  214         union {
  215                 struct {
  216                         struct pkthdr   m_pkthdr;       /* M_PKTHDR set */
  217                         union {
  218                                 struct m_ext    m_ext;  /* M_EXT set */
  219                                 char            m_pktdat[0];
  220                         };
  221                 };
  222                 char    m_dat[0];                       /* !M_PKTHDR, !M_EXT */
  223         };
  224 };
  225 
  226 /*
  227  * mbuf flags of global significance and layer crossing.
  228  * Those of only protocol/layer specific significance are to be mapped
  229  * to M_PROTO[1-12] and cleared at layer handoff boundaries.
  230  * NB: Limited to the lower 24 bits.
  231  */
  232 #define M_EXT           0x00000001 /* has associated external storage */
  233 #define M_PKTHDR        0x00000002 /* start of record */
  234 #define M_EOR           0x00000004 /* end of record */
  235 #define M_RDONLY        0x00000008 /* associated data is marked read-only */
  236 #define M_BCAST         0x00000010 /* send/received as link-level broadcast */
  237 #define M_MCAST         0x00000020 /* send/received as link-level multicast */
  238 #define M_PROMISC       0x00000040 /* packet was not for us */
  239 #define M_VLANTAG       0x00000080 /* ether_vtag is valid */
  240 #define M_UNUSED_8      0x00000100 /* --available-- */
  241 #define M_NOFREE        0x00000200 /* do not free mbuf, embedded in cluster */
  242 
  243 #define M_PROTO1        0x00001000 /* protocol-specific */
  244 #define M_PROTO2        0x00002000 /* protocol-specific */
  245 #define M_PROTO3        0x00004000 /* protocol-specific */
  246 #define M_PROTO4        0x00008000 /* protocol-specific */
  247 #define M_PROTO5        0x00010000 /* protocol-specific */
  248 #define M_PROTO6        0x00020000 /* protocol-specific */
  249 #define M_PROTO7        0x00040000 /* protocol-specific */
  250 #define M_PROTO8        0x00080000 /* protocol-specific */
  251 #define M_PROTO9        0x00100000 /* protocol-specific */
  252 #define M_PROTO10       0x00200000 /* protocol-specific */
  253 #define M_PROTO11       0x00400000 /* protocol-specific */
  254 #define M_PROTO12       0x00800000 /* protocol-specific */
  255 
  256 /*
  257  * Flags to purge when crossing layers.
  258  */
  259 #define M_PROTOFLAGS \
  260     (M_PROTO1|M_PROTO2|M_PROTO3|M_PROTO4|M_PROTO5|M_PROTO6|M_PROTO7|M_PROTO8|\
  261      M_PROTO9|M_PROTO10|M_PROTO11|M_PROTO12)
  262 
  263 /*
  264  * Flags preserved when copying m_pkthdr.
  265  */
  266 #define M_COPYFLAGS \
  267     (M_PKTHDR|M_EOR|M_RDONLY|M_BCAST|M_MCAST|M_PROMISC|M_VLANTAG| \
  268      M_PROTOFLAGS)
  269 
  270 /*
  271  * Mbuf flag description for use with printf(9) %b identifier.
  272  */
  273 #define M_FLAG_BITS \
  274     "\2\1M_EXT\2M_PKTHDR\3M_EOR\4M_RDONLY\5M_BCAST\6M_MCAST" \
  275     "\7M_PROMISC\10M_VLANTAG"
  276 #define M_FLAG_PROTOBITS \
  277     "\15M_PROTO1\16M_PROTO2\17M_PROTO3\20M_PROTO4\21M_PROTO5" \
  278     "\22M_PROTO6\23M_PROTO7\24M_PROTO8\25M_PROTO9\26M_PROTO10" \
  279     "\27M_PROTO11\30M_PROTO12"
  280 #define M_FLAG_PRINTF (M_FLAG_BITS M_FLAG_PROTOBITS)
  281 
  282 /*
  283  * Network interface cards are able to hash protocol fields (such as IPv4
  284  * addresses and TCP port numbers) classify packets into flows.  These flows
  285  * can then be used to maintain ordering while delivering packets to the OS
  286  * via parallel input queues, as well as to provide a stateless affinity
  287  * model.  NIC drivers can pass up the hash via m->m_pkthdr.flowid, and set
  288  * m_flag fields to indicate how the hash should be interpreted by the
  289  * network stack.
  290  *
  291  * Most NICs support RSS, which provides ordering and explicit affinity, and
  292  * use the hash m_flag bits to indicate what header fields were covered by
  293  * the hash.  M_HASHTYPE_OPAQUE can be set by non-RSS cards or configurations
  294  * that provide an opaque flow identifier, allowing for ordering and
  295  * distribution without explicit affinity.
  296  */
  297 /* Microsoft RSS standard hash types */
  298 #define M_HASHTYPE_NONE                 0
  299 #define M_HASHTYPE_RSS_IPV4             1       /* IPv4 2-tuple */
  300 #define M_HASHTYPE_RSS_TCP_IPV4         2       /* TCPv4 4-tuple */
  301 #define M_HASHTYPE_RSS_IPV6             3       /* IPv6 2-tuple */
  302 #define M_HASHTYPE_RSS_TCP_IPV6         4       /* TCPv6 4-tuple */
  303 #define M_HASHTYPE_RSS_IPV6_EX          5       /* IPv6 2-tuple + ext hdrs */
  304 #define M_HASHTYPE_RSS_TCP_IPV6_EX      6       /* TCPv6 4-tiple + ext hdrs */
  305 /* Non-standard RSS hash types */
  306 #define M_HASHTYPE_RSS_UDP_IPV4         7       /* IPv4 UDP 4-tuple */
  307 #define M_HASHTYPE_RSS_UDP_IPV4_EX      8       /* IPv4 UDP 4-tuple + ext hdrs */
  308 #define M_HASHTYPE_RSS_UDP_IPV6         9       /* IPv6 UDP 4-tuple */
  309 #define M_HASHTYPE_RSS_UDP_IPV6_EX      10      /* IPv6 UDP 4-tuple + ext hdrs */
  310 
  311 #define M_HASHTYPE_OPAQUE               255     /* ordering, not affinity */
  312 
  313 #define M_HASHTYPE_CLEAR(m)     ((m)->m_pkthdr.rsstype = 0)
  314 #define M_HASHTYPE_GET(m)       ((m)->m_pkthdr.rsstype)
  315 #define M_HASHTYPE_SET(m, v)    ((m)->m_pkthdr.rsstype = (v))
  316 #define M_HASHTYPE_TEST(m, v)   (M_HASHTYPE_GET(m) == (v))
  317 
  318 /*
  319  * COS/QOS class and quality of service tags.
  320  * It uses DSCP code points as base.
  321  */
  322 #define QOS_DSCP_CS0            0x00
  323 #define QOS_DSCP_DEF            QOS_DSCP_CS0
  324 #define QOS_DSCP_CS1            0x20
  325 #define QOS_DSCP_AF11           0x28
  326 #define QOS_DSCP_AF12           0x30
  327 #define QOS_DSCP_AF13           0x38
  328 #define QOS_DSCP_CS2            0x40
  329 #define QOS_DSCP_AF21           0x48
  330 #define QOS_DSCP_AF22           0x50
  331 #define QOS_DSCP_AF23           0x58
  332 #define QOS_DSCP_CS3            0x60
  333 #define QOS_DSCP_AF31           0x68
  334 #define QOS_DSCP_AF32           0x70
  335 #define QOS_DSCP_AF33           0x78
  336 #define QOS_DSCP_CS4            0x80
  337 #define QOS_DSCP_AF41           0x88
  338 #define QOS_DSCP_AF42           0x90
  339 #define QOS_DSCP_AF43           0x98
  340 #define QOS_DSCP_CS5            0xa0
  341 #define QOS_DSCP_EF             0xb8
  342 #define QOS_DSCP_CS6            0xc0
  343 #define QOS_DSCP_CS7            0xe0
  344 
  345 /*
  346  * External mbuf storage buffer types.
  347  */
  348 #define EXT_CLUSTER     1       /* mbuf cluster */
  349 #define EXT_SFBUF       2       /* sendfile(2)'s sf_buf */
  350 #define EXT_JUMBOP      3       /* jumbo cluster page sized */
  351 #define EXT_JUMBO9      4       /* jumbo cluster 9216 bytes */
  352 #define EXT_JUMBO16     5       /* jumbo cluster 16184 bytes */
  353 #define EXT_PACKET      6       /* mbuf+cluster from packet zone */
  354 #define EXT_MBUF        7       /* external mbuf reference (M_IOVEC) */
  355 #define EXT_SFBUF_NOCACHE 8     /* sendfile(2)'s sf_buf not to be cached */
  356 
  357 #define EXT_VENDOR1     224     /* for vendor-internal use */
  358 #define EXT_VENDOR2     225     /* for vendor-internal use */
  359 #define EXT_VENDOR3     226     /* for vendor-internal use */
  360 #define EXT_VENDOR4     227     /* for vendor-internal use */
  361 
  362 #define EXT_EXP1        244     /* for experimental use */
  363 #define EXT_EXP2        245     /* for experimental use */
  364 #define EXT_EXP3        246     /* for experimental use */
  365 #define EXT_EXP4        247     /* for experimental use */
  366 
  367 #define EXT_NET_DRV     252     /* custom ext_buf provided by net driver(s) */
  368 #define EXT_MOD_TYPE    253     /* custom module's ext_buf type */
  369 #define EXT_DISPOSABLE  254     /* can throw this buffer away w/page flipping */
  370 #define EXT_EXTREF      255     /* has externally maintained ext_cnt ptr */
  371 
  372 /*
  373  * Flags for external mbuf buffer types.
  374  * NB: limited to the lower 24 bits.
  375  */
  376 #define EXT_FLAG_EMBREF         0x000001        /* embedded ext_count */
  377 #define EXT_FLAG_EXTREF         0x000002        /* external ext_cnt, notyet */
  378 #define EXT_FLAG_NOFREE         0x000010        /* don't free mbuf to pool, notyet */
  379 
  380 #define EXT_FLAG_VENDOR1        0x010000        /* for vendor-internal use */
  381 #define EXT_FLAG_VENDOR2        0x020000        /* for vendor-internal use */
  382 #define EXT_FLAG_VENDOR3        0x040000        /* for vendor-internal use */
  383 #define EXT_FLAG_VENDOR4        0x080000        /* for vendor-internal use */
  384 
  385 #define EXT_FLAG_EXP1           0x100000        /* for experimental use */
  386 #define EXT_FLAG_EXP2           0x200000        /* for experimental use */
  387 #define EXT_FLAG_EXP3           0x400000        /* for experimental use */
  388 #define EXT_FLAG_EXP4           0x800000        /* for experimental use */
  389 
  390 /*
  391  * EXT flag description for use with printf(9) %b identifier.
  392  */
  393 #define EXT_FLAG_BITS \
  394     "\2\1EXT_FLAG_EMBREF\2EXT_FLAG_EXTREF\5EXT_FLAG_NOFREE" \
  395     "\21EXT_FLAG_VENDOR1\22EXT_FLAG_VENDOR2\23EXT_FLAG_VENDOR3" \
  396     "\24EXT_FLAG_VENDOR4\25EXT_FLAG_EXP1\26EXT_FLAG_EXP2\27EXT_FLAG_EXP3" \
  397     "\30EXT_FLAG_EXP4"
  398 
  399 /*
  400  * External reference/free functions.
  401  */
  402 void sf_ext_free(void *, void *);
  403 void sf_ext_free_nocache(void *, void *);
  404 
  405 /*
  406  * Flags indicating checksum, segmentation and other offload work to be
  407  * done, or already done, by hardware or lower layers.  It is split into
  408  * separate inbound and outbound flags.
  409  *
  410  * Outbound flags that are set by upper protocol layers requesting lower
  411  * layers, or ideally the hardware, to perform these offloading tasks.
  412  * For outbound packets this field and its flags can be directly tested
  413  * against ifnet if_hwassist.
  414  */
  415 #define CSUM_IP                 0x00000001      /* IP header checksum offload */
  416 #define CSUM_IP_UDP             0x00000002      /* UDP checksum offload */
  417 #define CSUM_IP_TCP             0x00000004      /* TCP checksum offload */
  418 #define CSUM_IP_SCTP            0x00000008      /* SCTP checksum offload */
  419 #define CSUM_IP_TSO             0x00000010      /* TCP segmentation offload */
  420 #define CSUM_IP_ISCSI           0x00000020      /* iSCSI checksum offload */
  421 
  422 #define CSUM_IP6_UDP            0x00000200      /* UDP checksum offload */
  423 #define CSUM_IP6_TCP            0x00000400      /* TCP checksum offload */
  424 #define CSUM_IP6_SCTP           0x00000800      /* SCTP checksum offload */
  425 #define CSUM_IP6_TSO            0x00001000      /* TCP segmentation offload */
  426 #define CSUM_IP6_ISCSI          0x00002000      /* iSCSI checksum offload */
  427 
  428 /* Inbound checksum support where the checksum was verified by hardware. */
  429 #define CSUM_L3_CALC            0x01000000      /* calculated layer 3 csum */
  430 #define CSUM_L3_VALID           0x02000000      /* checksum is correct */
  431 #define CSUM_L4_CALC            0x04000000      /* calculated layer 4 csum */
  432 #define CSUM_L4_VALID           0x08000000      /* checksum is correct */
  433 #define CSUM_L5_CALC            0x10000000      /* calculated layer 5 csum */
  434 #define CSUM_L5_VALID           0x20000000      /* checksum is correct */
  435 #define CSUM_COALESED           0x40000000      /* contains merged segments */
  436 
  437 /*
  438  * CSUM flag description for use with printf(9) %b identifier.
  439  */
  440 #define CSUM_BITS \
  441     "\2\1CSUM_IP\2CSUM_IP_UDP\3CSUM_IP_TCP\4CSUM_IP_SCTP\5CSUM_IP_TSO" \
  442     "\6CSUM_IP_ISCSI" \
  443     "\12CSUM_IP6_UDP\13CSUM_IP6_TCP\14CSUM_IP6_SCTP\15CSUM_IP6_TSO" \
  444     "\16CSUM_IP6_ISCSI" \
  445     "\31CSUM_L3_CALC\32CSUM_L3_VALID\33CSUM_L4_CALC\34CSUM_L4_VALID" \
  446     "\35CSUM_L5_CALC\36CSUM_L5_VALID\37CSUM_COALESED"
  447 
  448 /* CSUM flags compatibility mappings. */
  449 #define CSUM_IP_CHECKED         CSUM_L3_CALC
  450 #define CSUM_IP_VALID           CSUM_L3_VALID
  451 #define CSUM_DATA_VALID         CSUM_L4_VALID
  452 #define CSUM_PSEUDO_HDR         CSUM_L4_CALC
  453 #define CSUM_SCTP_VALID         CSUM_L4_VALID
  454 #define CSUM_DELAY_DATA         (CSUM_TCP|CSUM_UDP)
  455 #define CSUM_DELAY_IP           CSUM_IP         /* Only v4, no v6 IP hdr csum */
  456 #define CSUM_DELAY_DATA_IPV6    (CSUM_TCP_IPV6|CSUM_UDP_IPV6)
  457 #define CSUM_DATA_VALID_IPV6    CSUM_DATA_VALID
  458 #define CSUM_TCP                CSUM_IP_TCP
  459 #define CSUM_UDP                CSUM_IP_UDP
  460 #define CSUM_SCTP               CSUM_IP_SCTP
  461 #define CSUM_TSO                (CSUM_IP_TSO|CSUM_IP6_TSO)
  462 #define CSUM_UDP_IPV6           CSUM_IP6_UDP
  463 #define CSUM_TCP_IPV6           CSUM_IP6_TCP
  464 #define CSUM_SCTP_IPV6          CSUM_IP6_SCTP
  465 
  466 /*
  467  * mbuf types describing the content of the mbuf (including external storage).
  468  */
  469 #define MT_NOTMBUF      0       /* USED INTERNALLY ONLY! Object is not mbuf */
  470 #define MT_DATA         1       /* dynamic (data) allocation */
  471 #define MT_HEADER       MT_DATA /* packet header, use M_PKTHDR instead */
  472 
  473 #define MT_VENDOR1      4       /* for vendor-internal use */
  474 #define MT_VENDOR2      5       /* for vendor-internal use */
  475 #define MT_VENDOR3      6       /* for vendor-internal use */
  476 #define MT_VENDOR4      7       /* for vendor-internal use */
  477 
  478 #define MT_SONAME       8       /* socket name */
  479 
  480 #define MT_EXP1         9       /* for experimental use */
  481 #define MT_EXP2         10      /* for experimental use */
  482 #define MT_EXP3         11      /* for experimental use */
  483 #define MT_EXP4         12      /* for experimental use */
  484 
  485 #define MT_CONTROL      14      /* extra-data protocol message */
  486 #define MT_OOBDATA      15      /* expedited data  */
  487 #define MT_NTYPES       16      /* number of mbuf types for mbtypes[] */
  488 
  489 #define MT_NOINIT       255     /* Not a type but a flag to allocate
  490                                    a non-initialized mbuf */
  491 
  492 /*
  493  * String names of mbuf-related UMA(9) and malloc(9) types.  Exposed to
  494  * !_KERNEL so that monitoring tools can look up the zones with
  495  * libmemstat(3).
  496  */
  497 #define MBUF_MEM_NAME           "mbuf"
  498 #define MBUF_CLUSTER_MEM_NAME   "mbuf_cluster"
  499 #define MBUF_PACKET_MEM_NAME    "mbuf_packet"
  500 #define MBUF_JUMBOP_MEM_NAME    "mbuf_jumbo_page"
  501 #define MBUF_JUMBO9_MEM_NAME    "mbuf_jumbo_9k"
  502 #define MBUF_JUMBO16_MEM_NAME   "mbuf_jumbo_16k"
  503 #define MBUF_TAG_MEM_NAME       "mbuf_tag"
  504 #define MBUF_EXTREFCNT_MEM_NAME "mbuf_ext_refcnt"
  505 
  506 #ifdef _KERNEL
  507 
  508 #ifdef WITNESS
  509 #define MBUF_CHECKSLEEP(how) do {                                       \
  510         if (how == M_WAITOK)                                            \
  511                 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL,         \
  512                     "Sleeping in \"%s\"", __func__);                    \
  513 } while (0)
  514 #else
  515 #define MBUF_CHECKSLEEP(how)
  516 #endif
  517 
  518 /*
  519  * Network buffer allocation API
  520  *
  521  * The rest of it is defined in kern/kern_mbuf.c
  522  */
  523 extern uma_zone_t       zone_mbuf;
  524 extern uma_zone_t       zone_clust;
  525 extern uma_zone_t       zone_pack;
  526 extern uma_zone_t       zone_jumbop;
  527 extern uma_zone_t       zone_jumbo9;
  528 extern uma_zone_t       zone_jumbo16;
  529 
  530 void             mb_dupcl(struct mbuf *, struct mbuf *);
  531 void             mb_free_ext(struct mbuf *);
  532 void             m_adj(struct mbuf *, int);
  533 int              m_apply(struct mbuf *, int, int,
  534                     int (*)(void *, void *, u_int), void *);
  535 int              m_append(struct mbuf *, int, c_caddr_t);
  536 void             m_cat(struct mbuf *, struct mbuf *);
  537 void             m_catpkt(struct mbuf *, struct mbuf *);
  538 int              m_clget(struct mbuf *m, int how);
  539 void            *m_cljget(struct mbuf *m, int how, int size);
  540 struct mbuf     *m_collapse(struct mbuf *, int, int);
  541 void             m_copyback(struct mbuf *, int, int, c_caddr_t);
  542 void             m_copydata(const struct mbuf *, int, int, caddr_t);
  543 struct mbuf     *m_copym(struct mbuf *, int, int, int);
  544 struct mbuf     *m_copypacket(struct mbuf *, int);
  545 void             m_copy_pkthdr(struct mbuf *, struct mbuf *);
  546 struct mbuf     *m_copyup(struct mbuf *, int, int);
  547 struct mbuf     *m_defrag(struct mbuf *, int);
  548 void             m_demote_pkthdr(struct mbuf *);
  549 void             m_demote(struct mbuf *, int, int);
  550 struct mbuf     *m_devget(char *, int, int, struct ifnet *,
  551                     void (*)(char *, caddr_t, u_int));
  552 struct mbuf     *m_dup(const struct mbuf *, int);
  553 int              m_dup_pkthdr(struct mbuf *, const struct mbuf *, int);
  554 void             m_extadd(struct mbuf *, caddr_t, u_int,
  555                     void (*)(struct mbuf *, void *, void *), void *, void *,
  556                     int, int);
  557 u_int            m_fixhdr(struct mbuf *);
  558 struct mbuf     *m_fragment(struct mbuf *, int, int);
  559 void             m_freem(struct mbuf *);
  560 struct mbuf     *m_get2(int, int, short, int);
  561 struct mbuf     *m_getjcl(int, short, int, int);
  562 struct mbuf     *m_getm2(struct mbuf *, int, int, short, int);
  563 struct mbuf     *m_getptr(struct mbuf *, int, int *);
  564 u_int            m_length(struct mbuf *, struct mbuf **);
  565 int              m_mbuftouio(struct uio *, struct mbuf *, int);
  566 void             m_move_pkthdr(struct mbuf *, struct mbuf *);
  567 int              m_pkthdr_init(struct mbuf *, int);
  568 struct mbuf     *m_prepend(struct mbuf *, int, int);
  569 void             m_print(const struct mbuf *, int);
  570 struct mbuf     *m_pulldown(struct mbuf *, int, int, int *);
  571 struct mbuf     *m_pullup(struct mbuf *, int);
  572 int              m_sanity(struct mbuf *, int);
  573 struct mbuf     *m_split(struct mbuf *, int, int);
  574 struct mbuf     *m_uiotombuf(struct uio *, int, int, int, int);
  575 struct mbuf     *m_unshare(struct mbuf *, int);
  576 
  577 static __inline int
  578 m_gettype(int size)
  579 {
  580         int type;
  581 
  582         switch (size) {
  583         case MSIZE:
  584                 type = EXT_MBUF;
  585                 break;
  586         case MCLBYTES:
  587                 type = EXT_CLUSTER;
  588                 break;
  589 #if MJUMPAGESIZE != MCLBYTES
  590         case MJUMPAGESIZE:
  591                 type = EXT_JUMBOP;
  592                 break;
  593 #endif
  594         case MJUM9BYTES:
  595                 type = EXT_JUMBO9;
  596                 break;
  597         case MJUM16BYTES:
  598                 type = EXT_JUMBO16;
  599                 break;
  600         default:
  601                 panic("%s: invalid cluster size %d", __func__, size);
  602         }
  603 
  604         return (type);
  605 }
  606 
  607 /*
  608  * Associated an external reference counted buffer with an mbuf.
  609  */
  610 static __inline void
  611 m_extaddref(struct mbuf *m, caddr_t buf, u_int size, u_int *ref_cnt,
  612     void (*freef)(struct mbuf *, void *, void *), void *arg1, void *arg2)
  613 {
  614 
  615         KASSERT(ref_cnt != NULL, ("%s: ref_cnt not provided", __func__));
  616 
  617         atomic_add_int(ref_cnt, 1);
  618         m->m_flags |= M_EXT;
  619         m->m_ext.ext_buf = buf;
  620         m->m_ext.ext_cnt = ref_cnt;
  621         m->m_data = m->m_ext.ext_buf;
  622         m->m_ext.ext_size = size;
  623         m->m_ext.ext_free = freef;
  624         m->m_ext.ext_arg1 = arg1;
  625         m->m_ext.ext_arg2 = arg2;
  626         m->m_ext.ext_type = EXT_EXTREF;
  627         m->m_ext.ext_flags = 0;
  628 }
  629 
  630 static __inline uma_zone_t
  631 m_getzone(int size)
  632 {
  633         uma_zone_t zone;
  634 
  635         switch (size) {
  636         case MCLBYTES:
  637                 zone = zone_clust;
  638                 break;
  639 #if MJUMPAGESIZE != MCLBYTES
  640         case MJUMPAGESIZE:
  641                 zone = zone_jumbop;
  642                 break;
  643 #endif
  644         case MJUM9BYTES:
  645                 zone = zone_jumbo9;
  646                 break;
  647         case MJUM16BYTES:
  648                 zone = zone_jumbo16;
  649                 break;
  650         default:
  651                 panic("%s: invalid cluster size %d", __func__, size);
  652         }
  653 
  654         return (zone);
  655 }
  656 
  657 /*
  658  * Initialize an mbuf with linear storage.
  659  *
  660  * Inline because the consumer text overhead will be roughly the same to
  661  * initialize or call a function with this many parameters and M_PKTHDR
  662  * should go away with constant propagation for !MGETHDR.
  663  */
  664 static __inline int
  665 m_init(struct mbuf *m, int how, short type, int flags)
  666 {
  667         int error;
  668 
  669         m->m_next = NULL;
  670         m->m_nextpkt = NULL;
  671         m->m_data = m->m_dat;
  672         m->m_len = 0;
  673         m->m_flags = flags;
  674         m->m_type = type;
  675         if (flags & M_PKTHDR) {
  676                 if ((error = m_pkthdr_init(m, how)) != 0)
  677                         return (error);
  678         }
  679 
  680         return (0);
  681 }
  682 
  683 static __inline struct mbuf *
  684 m_get(int how, short type)
  685 {
  686         struct mb_args args;
  687 
  688         args.flags = 0;
  689         args.type = type;
  690         return (uma_zalloc_arg(zone_mbuf, &args, how));
  691 }
  692 
  693 static __inline struct mbuf *
  694 m_gethdr(int how, short type)
  695 {
  696         struct mb_args args;
  697 
  698         args.flags = M_PKTHDR;
  699         args.type = type;
  700         return (uma_zalloc_arg(zone_mbuf, &args, how));
  701 }
  702 
  703 static __inline struct mbuf *
  704 m_getcl(int how, short type, int flags)
  705 {
  706         struct mb_args args;
  707 
  708         args.flags = flags;
  709         args.type = type;
  710         return (uma_zalloc_arg(zone_pack, &args, how));
  711 }
  712 
  713 /*
  714  * XXX: m_cljset() is a dangerous API.  One must attach only a new,
  715  * unreferenced cluster to an mbuf(9).  It is not possible to assert
  716  * that, so care can be taken only by users of the API.
  717  */
  718 static __inline void
  719 m_cljset(struct mbuf *m, void *cl, int type)
  720 {
  721         int size;
  722 
  723         switch (type) {
  724         case EXT_CLUSTER:
  725                 size = MCLBYTES;
  726                 break;
  727 #if MJUMPAGESIZE != MCLBYTES
  728         case EXT_JUMBOP:
  729                 size = MJUMPAGESIZE;
  730                 break;
  731 #endif
  732         case EXT_JUMBO9:
  733                 size = MJUM9BYTES;
  734                 break;
  735         case EXT_JUMBO16:
  736                 size = MJUM16BYTES;
  737                 break;
  738         default:
  739                 panic("%s: unknown cluster type %d", __func__, type);
  740                 break;
  741         }
  742 
  743         m->m_data = m->m_ext.ext_buf = cl;
  744         m->m_ext.ext_free = m->m_ext.ext_arg1 = m->m_ext.ext_arg2 = NULL;
  745         m->m_ext.ext_size = size;
  746         m->m_ext.ext_type = type;
  747         m->m_ext.ext_flags = EXT_FLAG_EMBREF;
  748         m->m_ext.ext_count = 1;
  749         m->m_flags |= M_EXT;
  750 }
  751 
  752 static __inline void
  753 m_chtype(struct mbuf *m, short new_type)
  754 {
  755 
  756         m->m_type = new_type;
  757 }
  758 
  759 static __inline void
  760 m_clrprotoflags(struct mbuf *m)
  761 {
  762 
  763         while (m) {
  764                 m->m_flags &= ~M_PROTOFLAGS;
  765                 m = m->m_next;
  766         }
  767 }
  768 
  769 static __inline struct mbuf *
  770 m_last(struct mbuf *m)
  771 {
  772 
  773         while (m->m_next)
  774                 m = m->m_next;
  775         return (m);
  776 }
  777 
  778 static inline u_int
  779 m_extrefcnt(struct mbuf *m)
  780 {
  781 
  782         KASSERT(m->m_flags & M_EXT, ("%s: M_EXT missing", __func__));
  783 
  784         return ((m->m_ext.ext_flags & EXT_FLAG_EMBREF) ? m->m_ext.ext_count :
  785             *m->m_ext.ext_cnt);
  786 }
  787 
  788 /*
  789  * mbuf, cluster, and external object allocation macros (for compatibility
  790  * purposes).
  791  */
  792 #define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from))
  793 #define MGET(m, how, type)      ((m) = m_get((how), (type)))
  794 #define MGETHDR(m, how, type)   ((m) = m_gethdr((how), (type)))
  795 #define MCLGET(m, how)          m_clget((m), (how))
  796 #define MEXTADD(m, buf, size, free, arg1, arg2, flags, type)            \
  797     m_extadd((m), (caddr_t)(buf), (size), (free), (arg1), (arg2),       \
  798     (flags), (type))
  799 #define m_getm(m, len, how, type)                                       \
  800     m_getm2((m), (len), (how), (type), M_PKTHDR)
  801 
  802 /*
  803  * Evaluate TRUE if it's safe to write to the mbuf m's data region (this can
  804  * be both the local data payload, or an external buffer area, depending on
  805  * whether M_EXT is set).
  806  */
  807 #define M_WRITABLE(m)   (!((m)->m_flags & M_RDONLY) &&                  \
  808                          (!(((m)->m_flags & M_EXT)) ||                  \
  809                          (m_extrefcnt(m) == 1)))
  810 
  811 /* Check if the supplied mbuf has a packet header, or else panic. */
  812 #define M_ASSERTPKTHDR(m)                                               \
  813         KASSERT((m) != NULL && (m)->m_flags & M_PKTHDR,                 \
  814             ("%s: no mbuf packet header!", __func__))
  815 
  816 /*
  817  * Ensure that the supplied mbuf is a valid, non-free mbuf.
  818  *
  819  * XXX: Broken at the moment.  Need some UMA magic to make it work again.
  820  */
  821 #define M_ASSERTVALID(m)                                                \
  822         KASSERT((((struct mbuf *)m)->m_flags & 0) == 0,                 \
  823             ("%s: attempted use of a free mbuf!", __func__))
  824 
  825 /*
  826  * Return the address of the start of the buffer associated with an mbuf,
  827  * handling external storage, packet-header mbufs, and regular data mbufs.
  828  */
  829 #define M_START(m)                                                      \
  830         (((m)->m_flags & M_EXT) ? (m)->m_ext.ext_buf :                  \
  831          ((m)->m_flags & M_PKTHDR) ? &(m)->m_pktdat[0] :                \
  832          &(m)->m_dat[0])
  833 
  834 /*
  835  * Return the size of the buffer associated with an mbuf, handling external
  836  * storage, packet-header mbufs, and regular data mbufs.
  837  */
  838 #define M_SIZE(m)                                                       \
  839         (((m)->m_flags & M_EXT) ? (m)->m_ext.ext_size :                 \
  840          ((m)->m_flags & M_PKTHDR) ? MHLEN :                            \
  841          MLEN)
  842 
  843 /*
  844  * Set the m_data pointer of a newly allocated mbuf to place an object of the
  845  * specified size at the end of the mbuf, longword aligned.
  846  *
  847  * NB: Historically, we had M_ALIGN(), MH_ALIGN(), and MEXT_ALIGN() as
  848  * separate macros, each asserting that it was called at the proper moment.
  849  * This required callers to themselves test the storage type and call the
  850  * right one.  Rather than require callers to be aware of those layout
  851  * decisions, we centralize here.
  852  */
  853 static __inline void
  854 m_align(struct mbuf *m, int len)
  855 {
  856 #ifdef INVARIANTS
  857         const char *msg = "%s: not a virgin mbuf";
  858 #endif
  859         int adjust;
  860 
  861         KASSERT(m->m_data == M_START(m), (msg, __func__));
  862 
  863         adjust = M_SIZE(m) - len;
  864         m->m_data += adjust &~ (sizeof(long)-1);
  865 }
  866 
  867 #define M_ALIGN(m, len)         m_align(m, len)
  868 #define MH_ALIGN(m, len)        m_align(m, len)
  869 #define MEXT_ALIGN(m, len)      m_align(m, len)
  870 
  871 /*
  872  * Compute the amount of space available before the current start of data in
  873  * an mbuf.
  874  *
  875  * The M_WRITABLE() is a temporary, conservative safety measure: the burden
  876  * of checking writability of the mbuf data area rests solely with the caller.
  877  *
  878  * NB: In previous versions, M_LEADINGSPACE() would only check M_WRITABLE()
  879  * for mbufs with external storage.  We now allow mbuf-embedded data to be
  880  * read-only as well.
  881  */
  882 #define M_LEADINGSPACE(m)                                               \
  883         (M_WRITABLE(m) ? ((m)->m_data - M_START(m)) : 0)
  884 
  885 /*
  886  * Compute the amount of space available after the end of data in an mbuf.
  887  *
  888  * The M_WRITABLE() is a temporary, conservative safety measure: the burden
  889  * of checking writability of the mbuf data area rests solely with the caller.
  890  *
  891  * NB: In previous versions, M_TRAILINGSPACE() would only check M_WRITABLE()
  892  * for mbufs with external storage.  We now allow mbuf-embedded data to be
  893  * read-only as well.
  894  */
  895 #define M_TRAILINGSPACE(m)                                              \
  896         (M_WRITABLE(m) ?                                                \
  897             ((M_START(m) + M_SIZE(m)) - ((m)->m_data + (m)->m_len)) : 0)
  898 
  899 /*
  900  * Arrange to prepend space of size plen to mbuf m.  If a new mbuf must be
  901  * allocated, how specifies whether to wait.  If the allocation fails, the
  902  * original mbuf chain is freed and m is set to NULL.
  903  */
  904 #define M_PREPEND(m, plen, how) do {                                    \
  905         struct mbuf **_mmp = &(m);                                      \
  906         struct mbuf *_mm = *_mmp;                                       \
  907         int _mplen = (plen);                                            \
  908         int __mhow = (how);                                             \
  909                                                                         \
  910         MBUF_CHECKSLEEP(how);                                           \
  911         if (M_LEADINGSPACE(_mm) >= _mplen) {                            \
  912                 _mm->m_data -= _mplen;                                  \
  913                 _mm->m_len += _mplen;                                   \
  914         } else                                                          \
  915                 _mm = m_prepend(_mm, _mplen, __mhow);                   \
  916         if (_mm != NULL && _mm->m_flags & M_PKTHDR)                     \
  917                 _mm->m_pkthdr.len += _mplen;                            \
  918         *_mmp = _mm;                                                    \
  919 } while (0)
  920 
  921 /*
  922  * Change mbuf to new type.  This is a relatively expensive operation and
  923  * should be avoided.
  924  */
  925 #define MCHTYPE(m, t)   m_chtype((m), (t))
  926 
  927 /* Length to m_copy to copy all. */
  928 #define M_COPYALL       1000000000
  929 
  930 /* Compatibility with 4.3. */
  931 #define m_copy(m, o, l) m_copym((m), (o), (l), M_NOWAIT)
  932 
  933 extern int              max_datalen;    /* MHLEN - max_hdr */
  934 extern int              max_hdr;        /* Largest link + protocol header */
  935 extern int              max_linkhdr;    /* Largest link-level header */
  936 extern int              max_protohdr;   /* Largest protocol header */
  937 extern int              nmbclusters;    /* Maximum number of clusters */
  938 
  939 /*-
  940  * Network packets may have annotations attached by affixing a list of
  941  * "packet tags" to the pkthdr structure.  Packet tags are dynamically
  942  * allocated semi-opaque data structures that have a fixed header
  943  * (struct m_tag) that specifies the size of the memory block and a
  944  * <cookie,type> pair that identifies it.  The cookie is a 32-bit unique
  945  * unsigned value used to identify a module or ABI.  By convention this value
  946  * is chosen as the date+time that the module is created, expressed as the
  947  * number of seconds since the epoch (e.g., using date -u +'%s').  The type
  948  * value is an ABI/module-specific value that identifies a particular
  949  * annotation and is private to the module.  For compatibility with systems
  950  * like OpenBSD that define packet tags w/o an ABI/module cookie, the value
  951  * PACKET_ABI_COMPAT is used to implement m_tag_get and m_tag_find
  952  * compatibility shim functions and several tag types are defined below.
  953  * Users that do not require compatibility should use a private cookie value
  954  * so that packet tag-related definitions can be maintained privately.
  955  *
  956  * Note that the packet tag returned by m_tag_alloc has the default memory
  957  * alignment implemented by malloc.  To reference private data one can use a
  958  * construct like:
  959  *
  960  *      struct m_tag *mtag = m_tag_alloc(...);
  961  *      struct foo *p = (struct foo *)(mtag+1);
  962  *
  963  * if the alignment of struct m_tag is sufficient for referencing members of
  964  * struct foo.  Otherwise it is necessary to embed struct m_tag within the
  965  * private data structure to insure proper alignment; e.g.,
  966  *
  967  *      struct foo {
  968  *              struct m_tag    tag;
  969  *              ...
  970  *      };
  971  *      struct foo *p = (struct foo *) m_tag_alloc(...);
  972  *      struct m_tag *mtag = &p->tag;
  973  */
  974 
  975 /*
  976  * Persistent tags stay with an mbuf until the mbuf is reclaimed.  Otherwise
  977  * tags are expected to ``vanish'' when they pass through a network
  978  * interface.  For most interfaces this happens normally as the tags are
  979  * reclaimed when the mbuf is free'd.  However in some special cases
  980  * reclaiming must be done manually.  An example is packets that pass through
  981  * the loopback interface.  Also, one must be careful to do this when
  982  * ``turning around'' packets (e.g., icmp_reflect).
  983  *
  984  * To mark a tag persistent bit-or this flag in when defining the tag id.
  985  * The tag will then be treated as described above.
  986  */
  987 #define MTAG_PERSISTENT                         0x800
  988 
  989 #define PACKET_TAG_NONE                         0  /* Nadda */
  990 
  991 /* Packet tags for use with PACKET_ABI_COMPAT. */
  992 #define PACKET_TAG_IPSEC_IN_DONE                1  /* IPsec applied, in */
  993 #define PACKET_TAG_IPSEC_OUT_DONE               2  /* IPsec applied, out */
  994 #define PACKET_TAG_IPSEC_IN_CRYPTO_DONE         3  /* NIC IPsec crypto done */
  995 #define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED      4  /* NIC IPsec crypto req'ed */
  996 #define PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO     5  /* NIC notifies IPsec */
  997 #define PACKET_TAG_IPSEC_PENDING_TDB            6  /* Reminder to do IPsec */
  998 #define PACKET_TAG_BRIDGE                       7  /* Bridge processing done */
  999 #define PACKET_TAG_GIF                          8  /* GIF processing done */
 1000 #define PACKET_TAG_GRE                          9  /* GRE processing done */
 1001 #define PACKET_TAG_IN_PACKET_CHECKSUM           10 /* NIC checksumming done */
 1002 #define PACKET_TAG_ENCAP                        11 /* Encap.  processing */
 1003 #define PACKET_TAG_IPSEC_SOCKET                 12 /* IPSEC socket ref */
 1004 #define PACKET_TAG_IPSEC_HISTORY                13 /* IPSEC history */
 1005 #define PACKET_TAG_IPV6_INPUT                   14 /* IPV6 input processing */
 1006 #define PACKET_TAG_DUMMYNET                     15 /* dummynet info */
 1007 #define PACKET_TAG_DIVERT                       17 /* divert info */
 1008 #define PACKET_TAG_IPFORWARD                    18 /* ipforward info */
 1009 #define PACKET_TAG_MACLABEL     (19 | MTAG_PERSISTENT) /* MAC label */
 1010 #define PACKET_TAG_PF           (21 | MTAG_PERSISTENT) /* PF/ALTQ information */
 1011 #define PACKET_TAG_RTSOCKFAM                    25 /* rtsock sa family */
 1012 #define PACKET_TAG_IPOPTIONS                    27 /* Saved IP options */
 1013 #define PACKET_TAG_CARP                         28 /* CARP info */
 1014 #define PACKET_TAG_IPSEC_NAT_T_PORTS            29 /* two uint16_t */
 1015 #define PACKET_TAG_ND_OUTGOING                  30 /* ND outgoing */
 1016 
 1017 /* Specific cookies and tags. */
 1018 
 1019 /* Packet tag routines. */
 1020 struct m_tag    *m_tag_alloc(u_int32_t, int, int, int);
 1021 void             m_tag_delete(struct mbuf *, struct m_tag *);
 1022 void             m_tag_delete_chain(struct mbuf *, struct m_tag *);
 1023 void             m_tag_free_default(struct m_tag *);
 1024 struct m_tag    *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *);
 1025 struct m_tag    *m_tag_copy(struct m_tag *, int);
 1026 int              m_tag_copy_chain(struct mbuf *, const struct mbuf *, int);
 1027 void             m_tag_delete_nonpersistent(struct mbuf *);
 1028 
 1029 /*
 1030  * Initialize the list of tags associated with an mbuf.
 1031  */
 1032 static __inline void
 1033 m_tag_init(struct mbuf *m)
 1034 {
 1035 
 1036         SLIST_INIT(&m->m_pkthdr.tags);
 1037 }
 1038 
 1039 /*
 1040  * Set up the contents of a tag.  Note that this does not fill in the free
 1041  * method; the caller is expected to do that.
 1042  *
 1043  * XXX probably should be called m_tag_init, but that was already taken.
 1044  */
 1045 static __inline void
 1046 m_tag_setup(struct m_tag *t, u_int32_t cookie, int type, int len)
 1047 {
 1048 
 1049         t->m_tag_id = type;
 1050         t->m_tag_len = len;
 1051         t->m_tag_cookie = cookie;
 1052 }
 1053 
 1054 /*
 1055  * Reclaim resources associated with a tag.
 1056  */
 1057 static __inline void
 1058 m_tag_free(struct m_tag *t)
 1059 {
 1060 
 1061         (*t->m_tag_free)(t);
 1062 }
 1063 
 1064 /*
 1065  * Return the first tag associated with an mbuf.
 1066  */
 1067 static __inline struct m_tag *
 1068 m_tag_first(struct mbuf *m)
 1069 {
 1070 
 1071         return (SLIST_FIRST(&m->m_pkthdr.tags));
 1072 }
 1073 
 1074 /*
 1075  * Return the next tag in the list of tags associated with an mbuf.
 1076  */
 1077 static __inline struct m_tag *
 1078 m_tag_next(struct mbuf *m __unused, struct m_tag *t)
 1079 {
 1080 
 1081         return (SLIST_NEXT(t, m_tag_link));
 1082 }
 1083 
 1084 /*
 1085  * Prepend a tag to the list of tags associated with an mbuf.
 1086  */
 1087 static __inline void
 1088 m_tag_prepend(struct mbuf *m, struct m_tag *t)
 1089 {
 1090 
 1091         SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link);
 1092 }
 1093 
 1094 /*
 1095  * Unlink a tag from the list of tags associated with an mbuf.
 1096  */
 1097 static __inline void
 1098 m_tag_unlink(struct mbuf *m, struct m_tag *t)
 1099 {
 1100 
 1101         SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link);
 1102 }
 1103 
 1104 /* These are for OpenBSD compatibility. */
 1105 #define MTAG_ABI_COMPAT         0               /* compatibility ABI */
 1106 
 1107 static __inline struct m_tag *
 1108 m_tag_get(int type, int length, int wait)
 1109 {
 1110         return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait));
 1111 }
 1112 
 1113 static __inline struct m_tag *
 1114 m_tag_find(struct mbuf *m, int type, struct m_tag *start)
 1115 {
 1116         return (SLIST_EMPTY(&m->m_pkthdr.tags) ? (struct m_tag *)NULL :
 1117             m_tag_locate(m, MTAG_ABI_COMPAT, type, start));
 1118 }
 1119 
 1120 static __inline struct mbuf *
 1121 m_free(struct mbuf *m)
 1122 {
 1123         struct mbuf *n = m->m_next;
 1124 
 1125         if ((m->m_flags & (M_PKTHDR|M_NOFREE)) == (M_PKTHDR|M_NOFREE))
 1126                 m_tag_delete_chain(m, NULL);
 1127         if (m->m_flags & M_EXT)
 1128                 mb_free_ext(m);
 1129         else if ((m->m_flags & M_NOFREE) == 0)
 1130                 uma_zfree(zone_mbuf, m);
 1131         return (n);
 1132 }
 1133 
 1134 static __inline int
 1135 rt_m_getfib(struct mbuf *m)
 1136 {
 1137         KASSERT(m->m_flags & M_PKTHDR , ("Attempt to get FIB from non header mbuf."));
 1138         return (m->m_pkthdr.fibnum);
 1139 }
 1140 
 1141 #define M_GETFIB(_m)   rt_m_getfib(_m)
 1142 
 1143 #define M_SETFIB(_m, _fib) do {                                         \
 1144         KASSERT((_m)->m_flags & M_PKTHDR, ("Attempt to set FIB on non header mbuf."));  \
 1145         ((_m)->m_pkthdr.fibnum) = (_fib);                               \
 1146 } while (0)
 1147 
 1148 /* flags passed as first argument for "m_ether_tcpip_hash()" */
 1149 #define MBUF_HASHFLAG_L2        (1 << 2)
 1150 #define MBUF_HASHFLAG_L3        (1 << 3)
 1151 #define MBUF_HASHFLAG_L4        (1 << 4)
 1152 
 1153 /* mbuf hashing helper routines */
 1154 uint32_t        m_ether_tcpip_hash_init(void);
 1155 uint32_t        m_ether_tcpip_hash(const uint32_t, const struct mbuf *, const uint32_t);
 1156 
 1157 #ifdef MBUF_PROFILING
 1158  void m_profile(struct mbuf *m);
 1159  #define M_PROFILE(m) m_profile(m)
 1160 #else
 1161  #define M_PROFILE(m)
 1162 #endif
 1163 
 1164 struct mbufq {
 1165         STAILQ_HEAD(, mbuf)     mq_head;
 1166         int                     mq_len;
 1167         int                     mq_maxlen;
 1168 };
 1169 
 1170 static inline void
 1171 mbufq_init(struct mbufq *mq, int maxlen)
 1172 {
 1173 
 1174         STAILQ_INIT(&mq->mq_head);
 1175         mq->mq_maxlen = maxlen;
 1176         mq->mq_len = 0;
 1177 }
 1178 
 1179 static inline struct mbuf *
 1180 mbufq_flush(struct mbufq *mq)
 1181 {
 1182         struct mbuf *m;
 1183 
 1184         m = STAILQ_FIRST(&mq->mq_head);
 1185         STAILQ_INIT(&mq->mq_head);
 1186         mq->mq_len = 0;
 1187         return (m);
 1188 }
 1189 
 1190 static inline void
 1191 mbufq_drain(struct mbufq *mq)
 1192 {
 1193         struct mbuf *m, *n;
 1194 
 1195         n = mbufq_flush(mq);
 1196         while ((m = n) != NULL) {
 1197                 n = STAILQ_NEXT(m, m_stailqpkt);
 1198                 m_freem(m);
 1199         }
 1200 }
 1201 
 1202 static inline struct mbuf *
 1203 mbufq_first(const struct mbufq *mq)
 1204 {
 1205 
 1206         return (STAILQ_FIRST(&mq->mq_head));
 1207 }
 1208 
 1209 static inline struct mbuf *
 1210 mbufq_last(const struct mbufq *mq)
 1211 {
 1212 
 1213         return (STAILQ_LAST(&mq->mq_head, mbuf, m_stailqpkt));
 1214 }
 1215 
 1216 static inline int
 1217 mbufq_full(const struct mbufq *mq)
 1218 {
 1219 
 1220         return (mq->mq_len >= mq->mq_maxlen);
 1221 }
 1222 
 1223 static inline int
 1224 mbufq_len(const struct mbufq *mq)
 1225 {
 1226 
 1227         return (mq->mq_len);
 1228 }
 1229 
 1230 static inline int
 1231 mbufq_enqueue(struct mbufq *mq, struct mbuf *m)
 1232 {
 1233 
 1234         if (mbufq_full(mq))
 1235                 return (ENOBUFS);
 1236         STAILQ_INSERT_TAIL(&mq->mq_head, m, m_stailqpkt);
 1237         mq->mq_len++;
 1238         return (0);
 1239 }
 1240 
 1241 static inline struct mbuf *
 1242 mbufq_dequeue(struct mbufq *mq)
 1243 {
 1244         struct mbuf *m;
 1245 
 1246         m = STAILQ_FIRST(&mq->mq_head);
 1247         if (m) {
 1248                 STAILQ_REMOVE_HEAD(&mq->mq_head, m_stailqpkt);
 1249                 m->m_nextpkt = NULL;
 1250                 mq->mq_len--;
 1251         }
 1252         return (m);
 1253 }
 1254 
 1255 static inline void
 1256 mbufq_prepend(struct mbufq *mq, struct mbuf *m)
 1257 {
 1258 
 1259         STAILQ_INSERT_HEAD(&mq->mq_head, m, m_stailqpkt);
 1260         mq->mq_len++;
 1261 }
 1262 #endif /* _KERNEL */
 1263 #endif /* !_SYS_MBUF_H_ */

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