completion.h revision 219820 
141227Sjdp/*-
241227Sjdp * Copyright (c) 2010 Isilon Systems, Inc.
341227Sjdp * Copyright (c) 2010 iX Systems, Inc.
441227Sjdp * Copyright (c) 2010 Panasas, Inc.
541227Sjdp * All rights reserved.
641227Sjdp *
741227Sjdp * Redistribution and use in source and binary forms, with or without
841227Sjdp * modification, are permitted provided that the following conditions
941227Sjdp * are met:
1041227Sjdp * 1. Redistributions of source code must retain the above copyright
1141227Sjdp *    notice unmodified, this list of conditions, and the following
1241227Sjdp *    disclaimer.
1341227Sjdp * 2. Redistributions in binary form must reproduce the above copyright
1441227Sjdp *    notice, this list of conditions and the following disclaimer in the
1541227Sjdp *    documentation and/or other materials provided with the distribution.
1641227Sjdp *
1741227Sjdp * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
1841227Sjdp * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
1941227Sjdp * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
2041227Sjdp * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
2141227Sjdp * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
2241227Sjdp * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
2341227Sjdp * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
2441227Sjdp * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
2541227Sjdp * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
2641227Sjdp * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
2741227Sjdp */
2841227Sjdp#ifndef	_LINUX_COMPLETION_H_
2941227Sjdp#define	_LINUX_COMPLETION_H_
3041227Sjdp
3141227Sjdp#include <linux/errno.h>
3241227Sjdp#include <linux/sched.h>
3341227Sjdp#include <linux/wait.h>
3441227Sjdp
3541227Sjdp#include <sys/param.h>
3641227Sjdp#include <sys/systm.h>
3741227Sjdp#include <sys/sleepqueue.h>
3841227Sjdp#include <sys/kernel.h>
3941227Sjdp#include <sys/proc.h>
4041227Sjdp
4141227Sjdpstruct completion {
42	unsigned int done;
43};
44
45#define	INIT_COMPLETION(c)	((c).done = 0)
46#define	init_completion(c)	((c)->done = 0)
47
48static inline void
49_complete_common(struct completion *c, int all)
50{
51	int wakeup_swapper;
52
53	sleepq_lock(c);
54	c->done++;
55	if (all)
56		wakeup_swapper = sleepq_broadcast(c, SLEEPQ_SLEEP, 0, 0);
57	else
58		wakeup_swapper = sleepq_signal(c, SLEEPQ_SLEEP, 0, 0);
59	sleepq_release(c);
60	if (wakeup_swapper)
61		kick_proc0();
62}
63
64#define	complete(c)	_complete_common(c, 0)
65#define	complete_all(c)	_complete_common(c, 1)
66
67/*
68 * Indefinite wait for done != 0 with or without signals.
69 */
70static inline long
71_wait_for_common(struct completion *c, int flags)
72{
73
74	flags |= SLEEPQ_SLEEP;
75	for (;;) {
76		sleepq_lock(c);
77		if (c->done)
78			break;
79		sleepq_add(c, NULL, "completion", flags, 0);
80		if (flags & SLEEPQ_INTERRUPTIBLE) {
81			if (sleepq_wait_sig(c, 0) != 0)
82				return (-ERESTARTSYS);
83		} else
84			sleepq_wait(c, 0);
85	}
86	c->done--;
87	sleepq_release(c);
88
89	return (0);
90}
91
92#define	wait_for_completion(c)	_wait_for_common(c, 0)
93#define	wait_for_completion_interuptible(c)				\
94	_wait_for_common(c, SLEEPQ_INTERRUPTIBLE)
95
96static inline long
97_wait_for_timeout_common(struct completion *c, long timeout, int flags)
98{
99	long end;
100
101	end = ticks + timeout;
102	flags |= SLEEPQ_SLEEP;
103	for (;;) {
104		sleepq_lock(c);
105		if (c->done)
106			break;
107		sleepq_add(c, NULL, "completion", flags, 0);
108		sleepq_set_timeout(c, end - ticks);
109		if (flags & SLEEPQ_INTERRUPTIBLE) {
110			if (sleepq_timedwait_sig(c, 0) != 0)
111				return (-ERESTARTSYS);
112		} else
113			sleepq_timedwait(c, 0);
114	}
115	c->done--;
116	sleepq_release(c);
117	timeout = end - ticks;
118
119	return (timeout > 0 ? timeout : 1);
120}
121
122#define	wait_for_completion_timeout(c, timeout)				\
123	_wait_for_timeout_common(c, timeout, 0)
124#define	wait_for_completion_interruptible_timeout(c, timeout)		\
125	_wait_for_timeout_common(c, timeout, SLEEPQ_INTERRUPTIBLE)
126
127static inline int
128try_wait_for_completion(struct completion *c)
129{
130	int isdone;
131
132	isdone = 1;
133	sleepq_lock(c);
134	if (c->done)
135		c->done--;
136	else
137		isdone = 0;
138	sleepq_release(c);
139	return (isdone);
140}
141
142static inline int
143completion_done(struct completion *c)
144{
145	int isdone;
146
147	isdone = 1;
148	sleepq_lock(c);
149	if (c->done == 0)
150		isdone = 0;
151	sleepq_release(c);
152	return (isdone);
153}
154
155#endif	/* _LINUX_COMPLETION_H_ */
156