sockbuf.h revision 264080
1/*- 2 * Copyright (c) 1982, 1986, 1990, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)socketvar.h 8.3 (Berkeley) 2/19/95 30 * 31 * $FreeBSD: stable/10/sys/sys/sockbuf.h 264080 2014-04-03 16:57:16Z asomers $ 32 */ 33#ifndef _SYS_SOCKBUF_H_ 34#define _SYS_SOCKBUF_H_ 35#include <sys/selinfo.h> /* for struct selinfo */ 36#include <sys/_lock.h> 37#include <sys/_mutex.h> 38#include <sys/_sx.h> 39 40#define SB_MAX (2*1024*1024) /* default for max chars in sockbuf */ 41 42/* 43 * Constants for sb_flags field of struct sockbuf. 44 */ 45#define SB_WAIT 0x04 /* someone is waiting for data/space */ 46#define SB_SEL 0x08 /* someone is selecting */ 47#define SB_ASYNC 0x10 /* ASYNC I/O, need signals */ 48#define SB_UPCALL 0x20 /* someone wants an upcall */ 49#define SB_NOINTR 0x40 /* operations not interruptible */ 50#define SB_AIO 0x80 /* AIO operations queued */ 51#define SB_KNOTE 0x100 /* kernel note attached */ 52#define SB_NOCOALESCE 0x200 /* don't coalesce new data into existing mbufs */ 53#define SB_IN_TOE 0x400 /* socket buffer is in the middle of an operation */ 54#define SB_AUTOSIZE 0x800 /* automatically size socket buffer */ 55#define SB_STOP 0x1000 /* backpressure indicator */ 56 57#define SBS_CANTSENDMORE 0x0010 /* can't send more data to peer */ 58#define SBS_CANTRCVMORE 0x0020 /* can't receive more data from peer */ 59#define SBS_RCVATMARK 0x0040 /* at mark on input */ 60 61struct mbuf; 62struct sockaddr; 63struct socket; 64struct thread; 65 66struct xsockbuf { 67 u_int sb_cc; 68 u_int sb_hiwat; 69 u_int sb_mbcnt; 70 u_int sb_mcnt; 71 u_int sb_ccnt; 72 u_int sb_mbmax; 73 int sb_lowat; 74 int sb_timeo; 75 short sb_flags; 76}; 77 78/* 79 * Variables for socket buffering. 80 */ 81struct sockbuf { 82 struct selinfo sb_sel; /* process selecting read/write */ 83 struct mtx sb_mtx; /* sockbuf lock */ 84 struct sx sb_sx; /* prevent I/O interlacing */ 85 short sb_state; /* (c/d) socket state on sockbuf */ 86#define sb_startzero sb_mb 87 struct mbuf *sb_mb; /* (c/d) the mbuf chain */ 88 struct mbuf *sb_mbtail; /* (c/d) the last mbuf in the chain */ 89 struct mbuf *sb_lastrecord; /* (c/d) first mbuf of last 90 * record in socket buffer */ 91 struct mbuf *sb_sndptr; /* (c/d) pointer into mbuf chain */ 92 u_int sb_sndptroff; /* (c/d) byte offset of ptr into chain */ 93 u_int sb_cc; /* (c/d) actual chars in buffer */ 94 u_int sb_hiwat; /* (c/d) max actual char count */ 95 u_int sb_mbcnt; /* (c/d) chars of mbufs used */ 96 u_int sb_mcnt; /* (c/d) number of mbufs in buffer */ 97 u_int sb_ccnt; /* (c/d) number of clusters in buffer */ 98 u_int sb_mbmax; /* (c/d) max chars of mbufs to use */ 99 u_int sb_ctl; /* (c/d) non-data chars in buffer */ 100 int sb_lowat; /* (c/d) low water mark */ 101 sbintime_t sb_timeo; /* (c/d) timeout for read/write */ 102 short sb_flags; /* (c/d) flags, see below */ 103 int (*sb_upcall)(struct socket *, void *, int); /* (c/d) */ 104 void *sb_upcallarg; /* (c/d) */ 105}; 106 107#ifdef _KERNEL 108 109/* 110 * Per-socket buffer mutex used to protect most fields in the socket 111 * buffer. 112 */ 113#define SOCKBUF_MTX(_sb) (&(_sb)->sb_mtx) 114#define SOCKBUF_LOCK_INIT(_sb, _name) \ 115 mtx_init(SOCKBUF_MTX(_sb), _name, NULL, MTX_DEF) 116#define SOCKBUF_LOCK_DESTROY(_sb) mtx_destroy(SOCKBUF_MTX(_sb)) 117#define SOCKBUF_LOCK(_sb) mtx_lock(SOCKBUF_MTX(_sb)) 118#define SOCKBUF_OWNED(_sb) mtx_owned(SOCKBUF_MTX(_sb)) 119#define SOCKBUF_UNLOCK(_sb) mtx_unlock(SOCKBUF_MTX(_sb)) 120#define SOCKBUF_LOCK_ASSERT(_sb) mtx_assert(SOCKBUF_MTX(_sb), MA_OWNED) 121#define SOCKBUF_UNLOCK_ASSERT(_sb) mtx_assert(SOCKBUF_MTX(_sb), MA_NOTOWNED) 122 123void sbappend(struct sockbuf *sb, struct mbuf *m); 124void sbappend_locked(struct sockbuf *sb, struct mbuf *m); 125void sbappendstream(struct sockbuf *sb, struct mbuf *m); 126void sbappendstream_locked(struct sockbuf *sb, struct mbuf *m); 127int sbappendaddr(struct sockbuf *sb, const struct sockaddr *asa, 128 struct mbuf *m0, struct mbuf *control); 129int sbappendaddr_locked(struct sockbuf *sb, const struct sockaddr *asa, 130 struct mbuf *m0, struct mbuf *control); 131int sbappendaddr_nospacecheck_locked(struct sockbuf *sb, 132 const struct sockaddr *asa, struct mbuf *m0, struct mbuf *control); 133int sbappendcontrol(struct sockbuf *sb, struct mbuf *m0, 134 struct mbuf *control); 135int sbappendcontrol_locked(struct sockbuf *sb, struct mbuf *m0, 136 struct mbuf *control); 137void sbappendrecord(struct sockbuf *sb, struct mbuf *m0); 138void sbappendrecord_locked(struct sockbuf *sb, struct mbuf *m0); 139void sbcheck(struct sockbuf *sb); 140void sbcompress(struct sockbuf *sb, struct mbuf *m, struct mbuf *n); 141struct mbuf * 142 sbcreatecontrol(caddr_t p, int size, int type, int level); 143void sbdestroy(struct sockbuf *sb, struct socket *so); 144void sbdrop(struct sockbuf *sb, int len); 145void sbdrop_locked(struct sockbuf *sb, int len); 146struct mbuf * 147 sbcut_locked(struct sockbuf *sb, int len); 148void sbdroprecord(struct sockbuf *sb); 149void sbdroprecord_locked(struct sockbuf *sb); 150void sbflush(struct sockbuf *sb); 151void sbflush_locked(struct sockbuf *sb); 152void sbrelease(struct sockbuf *sb, struct socket *so); 153void sbrelease_internal(struct sockbuf *sb, struct socket *so); 154void sbrelease_locked(struct sockbuf *sb, struct socket *so); 155int sbreserve(struct sockbuf *sb, u_long cc, struct socket *so, 156 struct thread *td); 157int sbreserve_locked(struct sockbuf *sb, u_long cc, struct socket *so, 158 struct thread *td); 159struct mbuf * 160 sbsndptr(struct sockbuf *sb, u_int off, u_int len, u_int *moff); 161void sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb); 162int sbwait(struct sockbuf *sb); 163int sblock(struct sockbuf *sb, int flags); 164void sbunlock(struct sockbuf *sb); 165 166/* 167 * How much space is there in a socket buffer (so->so_snd or so->so_rcv)? 168 * This is problematical if the fields are unsigned, as the space might 169 * still be negative (cc > hiwat or mbcnt > mbmax). Should detect 170 * overflow and return 0. Should use "lmin" but it doesn't exist now. 171 */ 172static __inline 173long 174sbspace(struct sockbuf *sb) 175{ 176 long bleft; 177 long mleft; 178 179 if (sb->sb_flags & SB_STOP) 180 return(0); 181 bleft = sb->sb_hiwat - sb->sb_cc; 182 mleft = sb->sb_mbmax - sb->sb_mbcnt; 183 return((bleft < mleft) ? bleft : mleft); 184} 185 186/* adjust counters in sb reflecting allocation of m */ 187#define sballoc(sb, m) { \ 188 (sb)->sb_cc += (m)->m_len; \ 189 if ((m)->m_type != MT_DATA && (m)->m_type != MT_OOBDATA) \ 190 (sb)->sb_ctl += (m)->m_len; \ 191 (sb)->sb_mbcnt += MSIZE; \ 192 (sb)->sb_mcnt += 1; \ 193 if ((m)->m_flags & M_EXT) { \ 194 (sb)->sb_mbcnt += (m)->m_ext.ext_size; \ 195 (sb)->sb_ccnt += 1; \ 196 } \ 197} 198 199/* adjust counters in sb reflecting freeing of m */ 200#define sbfree(sb, m) { \ 201 (sb)->sb_cc -= (m)->m_len; \ 202 if ((m)->m_type != MT_DATA && (m)->m_type != MT_OOBDATA) \ 203 (sb)->sb_ctl -= (m)->m_len; \ 204 (sb)->sb_mbcnt -= MSIZE; \ 205 (sb)->sb_mcnt -= 1; \ 206 if ((m)->m_flags & M_EXT) { \ 207 (sb)->sb_mbcnt -= (m)->m_ext.ext_size; \ 208 (sb)->sb_ccnt -= 1; \ 209 } \ 210 if ((sb)->sb_sndptr == (m)) { \ 211 (sb)->sb_sndptr = NULL; \ 212 (sb)->sb_sndptroff = 0; \ 213 } \ 214 if ((sb)->sb_sndptroff != 0) \ 215 (sb)->sb_sndptroff -= (m)->m_len; \ 216} 217 218#define SB_EMPTY_FIXUP(sb) do { \ 219 if ((sb)->sb_mb == NULL) { \ 220 (sb)->sb_mbtail = NULL; \ 221 (sb)->sb_lastrecord = NULL; \ 222 } \ 223} while (/*CONSTCOND*/0) 224 225#ifdef SOCKBUF_DEBUG 226void sblastrecordchk(struct sockbuf *, const char *, int); 227#define SBLASTRECORDCHK(sb) sblastrecordchk((sb), __FILE__, __LINE__) 228 229void sblastmbufchk(struct sockbuf *, const char *, int); 230#define SBLASTMBUFCHK(sb) sblastmbufchk((sb), __FILE__, __LINE__) 231#else 232#define SBLASTRECORDCHK(sb) /* nothing */ 233#define SBLASTMBUFCHK(sb) /* nothing */ 234#endif /* SOCKBUF_DEBUG */ 235 236#endif /* _KERNEL */ 237 238#endif /* _SYS_SOCKBUF_H_ */ 239