forked from DragonFlyBSD/DragonFlyBSD
/
socketvar2.h
122 lines (112 loc) · 3.68 KB
/
socketvar2.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
/*-
* Copyright (c) 1982, 1986, 1990, 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.
*
* @(#)socketvar.h 8.3 (Berkeley) 2/19/95
* $FreeBSD: src/sys/sys/socketvar.h,v 1.46.2.10 2003/08/24 08:24:39 hsu Exp $
*/
#ifndef _SYS_SOCKETVAR2_H_
#define _SYS_SOCKETVAR2_H_
#ifndef _SYS_SOCKETVAR_H_
#include <sys/socketvar.h>
#endif
#ifndef _SYS_SYSTM_H_
#include <sys/systm.h>
#endif
#ifndef _SYS_MALLOC_H_
#include <sys/malloc.h>
#endif
#include <machine/atomic.h>
/*
* Acquire a lock on a signalsockbuf, sleep if the lock is already held.
* The sleep is interruptable unless SSB_NOINTR is set in the ssb.
*
* We also acquire the token on success. This token is used to interlock
* frontend/backend operations until the sockbuf itself can be made mpsafe.
*
* Returns 0 on success, non-zero if the lock could not be acquired.
*/
static __inline int
ssb_lock(struct signalsockbuf *ssb, int wf)
{
uint32_t flags;
for (;;) {
flags = ssb->ssb_flags;
cpu_ccfence();
if (flags & SSB_LOCK) {
if (wf == M_WAITOK)
return _ssb_lock(ssb);
return EWOULDBLOCK;
}
if (atomic_cmpset_int(&ssb->ssb_flags, flags, flags|SSB_LOCK)) {
lwkt_gettoken(&ssb->ssb_token);
return(0);
}
}
}
/*
* Release a previously acquired lock on a signalsockbuf.
*
* Interlocked wakeup if SSB_WANT was also set.
*/
static __inline void
ssb_unlock(struct signalsockbuf *ssb)
{
uint32_t flags;
KKASSERT(ssb->ssb_flags & SSB_LOCK);
lwkt_reltoken(&ssb->ssb_token);
for (;;) {
flags = ssb->ssb_flags;
cpu_ccfence();
if (atomic_cmpset_int(&ssb->ssb_flags, flags,
flags & ~(SSB_LOCK | SSB_WANT))) {
if (flags & SSB_WANT)
wakeup(&ssb->ssb_flags);
break;
}
}
}
static __inline void
sosetstate(struct socket *so, short state)
{
atomic_set_short(&so->so_state, state);
}
static __inline void
soclrstate(struct socket *so, short state)
{
atomic_clear_short(&so->so_state, state);
}
static __inline void
soreference(struct socket *so)
{
atomic_add_int(&so->so_refs, 1);
}
#endif