1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2020-2021 Bjoern A. Zeeb
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  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * $FreeBSD$
28  */
29 
30 #ifndef	_LINUXKPI_LINUX_IOPOLL_H
31 #define	_LINUXKPI_LINUX_IOPOLL_H
32 
33 #include <sys/types.h>
34 #include <sys/time.h>
35 #include <linux/delay.h>
36 
37 #define	read_poll_timeout(_pollfp, _var, _cond, _us, _to, _early_sleep, ...)	\
38 ({										\
39 	struct timeval __now, __end;						\
40 	if (_to) {								\
41 		__end.tv_sec = (_to) / USEC_PER_SEC;				\
42 		__end.tv_usec = (_to) % USEC_PER_SEC;				\
43 		microtime(&__now);						\
44 		timevaladd(&__end, &__now);					\
45 	}									\
46 										\
47 	if ((_early_sleep) && (_us) > 0)					\
48 		usleep_range(_us, _us);						\
49 	do {									\
50 		(_var) = _pollfp(__VA_ARGS__);					\
51 		if (_cond)							\
52 			break;							\
53 		if (_to) {							\
54 			microtime(&__now);					\
55 			if (timevalcmp(&__now, &__end, >))			\
56 				break;						\
57 		}								\
58 		if ((_us) != 0)							\
59 			usleep_range(_us, _us);					\
60 	} while (1);								\
61 	(_cond) ? 0 : (-ETIMEDOUT);						\
62 })
63 
64 #define readx_poll_timeout(_pollfp, _addr, _var, _cond, _us, _to)		\
65 	read_poll_timeout(_pollfp, _var, _cond, _us, _to, false, _addr)
66 
67 #define	read_poll_timeout_atomic(_pollfp, _var, _cond, _us, _to, _early_sleep, ...)	\
68 ({										\
69 	struct timeval __now, __end;						\
70 	if (_to) {								\
71 		__end.tv_sec = (_to) / USEC_PER_SEC;				\
72 		__end.tv_usec = (_to) % USEC_PER_SEC;				\
73 		microtime(&__now);						\
74 		timevaladd(&__end, &__now);					\
75 	}									\
76 										\
77 	if ((_early_sleep) && (_us) > 0)					\
78 		DELAY(_us);							\
79 	do {									\
80 		(_var) = _pollfp(__VA_ARGS__);					\
81 		if (_cond)							\
82 			break;							\
83 		if (_to) {							\
84 			microtime(&__now);					\
85 			if (timevalcmp(&__now, &__end, >))			\
86 				break;						\
87 		}								\
88 		if ((_us) != 0)							\
89 			DELAY(_us);						\
90 	} while (1);								\
91 	(_cond) ? 0 : (-ETIMEDOUT);						\
92 })
93 
94 #endif	/* _LINUXKPI_LINUX_IOPOLL_H */
95