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 * $FreeBSD$
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
61 struct mbuf;
62 struct sockaddr;
63 struct socket;
64 struct thread;
65
66 struct 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 */
81 struct 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
123 void sbappend(struct sockbuf *sb, struct mbuf *m);
124 void sbappend_locked(struct sockbuf *sb, struct mbuf *m);
125 void sbappendstream(struct sockbuf *sb, struct mbuf *m);
126 void sbappendstream_locked(struct sockbuf *sb, struct mbuf *m);
127 int sbappendaddr(struct sockbuf *sb, const struct sockaddr *asa,
128 struct mbuf *m0, struct mbuf *control);
129 int sbappendaddr_locked(struct sockbuf *sb, const struct sockaddr *asa,
130 struct mbuf *m0, struct mbuf *control);
131 int sbappendaddr_nospacecheck_locked(struct sockbuf *sb,
132 const struct sockaddr *asa, struct mbuf *m0, struct mbuf *control);
133 int sbappendcontrol(struct sockbuf *sb, struct mbuf *m0,
134 struct mbuf *control);
135 int sbappendcontrol_locked(struct sockbuf *sb, struct mbuf *m0,
136 struct mbuf *control);
137 void sbappendrecord(struct sockbuf *sb, struct mbuf *m0);
138 void sbappendrecord_locked(struct sockbuf *sb, struct mbuf *m0);
139 void sbcheck(struct sockbuf *sb);
140 void sbcompress(struct sockbuf *sb, struct mbuf *m, struct mbuf *n);
141 struct mbuf *
142 sbcreatecontrol(caddr_t p, int size, int type, int level);
143 void sbdestroy(struct sockbuf *sb, struct socket *so);
144 void sbdrop(struct sockbuf *sb, int len);
145 void sbdrop_locked(struct sockbuf *sb, int len);
146 struct mbuf *
147 sbcut_locked(struct sockbuf *sb, int len);
148 void sbdroprecord(struct sockbuf *sb);
149 void sbdroprecord_locked(struct sockbuf *sb);
150 void sbflush(struct sockbuf *sb);
151 void sbflush_locked(struct sockbuf *sb);
152 void sbrelease(struct sockbuf *sb, struct socket *so);
153 void sbrelease_internal(struct sockbuf *sb, struct socket *so);
154 void sbrelease_locked(struct sockbuf *sb, struct socket *so);
155 int sbreserve(struct sockbuf *sb, u_long cc, struct socket *so,
156 struct thread *td);
157 int sbreserve_locked(struct sockbuf *sb, u_long cc, struct socket *so,
158 struct thread *td);
159 struct mbuf *
160 sbsndptr(struct sockbuf *sb, u_int off, u_int len, u_int *moff);
161 struct mbuf *
162 sbsndmbuf(struct sockbuf *sb, u_int off, u_int *moff);
163 void sbtoxsockbuf(struct sockbuf *sb, struct xsockbuf *xsb);
164 int sbwait(struct sockbuf *sb);
165 int sblock(struct sockbuf *sb, int flags);
166 void sbunlock(struct sockbuf *sb);
167
168 /*
169 * How much space is there in a socket buffer (so->so_snd or so->so_rcv)?
170 * This is problematical if the fields are unsigned, as the space might
171 * still be negative (cc > hiwat or mbcnt > mbmax). Should detect
172 * overflow and return 0. Should use "lmin" but it doesn't exist now.
173 */
174 static __inline
175 long
sbspace(struct sockbuf * sb)176 sbspace(struct sockbuf *sb)
177 {
178 int bleft, mleft; /* size should match sockbuf fields */
179
180 if (sb->sb_flags & SB_STOP)
181 return(0);
182 bleft = sb->sb_hiwat - sb->sb_cc;
183 mleft = sb->sb_mbmax - sb->sb_mbcnt;
184 return((bleft < mleft) ? bleft : mleft);
185 }
186
187 /* adjust counters in sb reflecting allocation of m */
188 #define sballoc(sb, m) { \
189 (sb)->sb_cc += (m)->m_len; \
190 if ((m)->m_type != MT_DATA && (m)->m_type != MT_OOBDATA) \
191 (sb)->sb_ctl += (m)->m_len; \
192 (sb)->sb_mbcnt += MSIZE; \
193 (sb)->sb_mcnt += 1; \
194 if ((m)->m_flags & M_EXT) { \
195 (sb)->sb_mbcnt += (m)->m_ext.ext_size; \
196 (sb)->sb_ccnt += 1; \
197 } \
198 }
199
200 /* adjust counters in sb reflecting freeing of m */
201 #define sbfree(sb, m) { \
202 (sb)->sb_cc -= (m)->m_len; \
203 if ((m)->m_type != MT_DATA && (m)->m_type != MT_OOBDATA) \
204 (sb)->sb_ctl -= (m)->m_len; \
205 (sb)->sb_mbcnt -= MSIZE; \
206 (sb)->sb_mcnt -= 1; \
207 if ((m)->m_flags & M_EXT) { \
208 (sb)->sb_mbcnt -= (m)->m_ext.ext_size; \
209 (sb)->sb_ccnt -= 1; \
210 } \
211 if ((sb)->sb_sndptr == (m)) { \
212 (sb)->sb_sndptr = NULL; \
213 (sb)->sb_sndptroff = 0; \
214 } \
215 if ((sb)->sb_sndptroff != 0) \
216 (sb)->sb_sndptroff -= (m)->m_len; \
217 }
218
219 #define SB_EMPTY_FIXUP(sb) do { \
220 if ((sb)->sb_mb == NULL) { \
221 (sb)->sb_mbtail = NULL; \
222 (sb)->sb_lastrecord = NULL; \
223 } \
224 } while (/*CONSTCOND*/0)
225
226 #ifdef SOCKBUF_DEBUG
227 void sblastrecordchk(struct sockbuf *, const char *, int);
228 #define SBLASTRECORDCHK(sb) sblastrecordchk((sb), __FILE__, __LINE__)
229
230 void sblastmbufchk(struct sockbuf *, const char *, int);
231 #define SBLASTMBUFCHK(sb) sblastmbufchk((sb), __FILE__, __LINE__)
232 #else
233 #define SBLASTRECORDCHK(sb) /* nothing */
234 #define SBLASTMBUFCHK(sb) /* nothing */
235 #endif /* SOCKBUF_DEBUG */
236
237 #endif /* _KERNEL */
238
239 #endif /* _SYS_SOCKBUF_H_ */
240