1/* $NetBSD: aio.h,v 1.13 2016/04/09 19:55:33 riastradh Exp $ */
2
3/*
4 * Copyright (c) 2007, Mindaugas Rasiukevicius <rmind at NetBSD org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#ifndef _SYS_AIO_H_
30#define _SYS_AIO_H_
31
32#include <sys/types.h>
33#include <sys/signal.h>
34
35/* Returned by aio_cancel() */
36#define AIO_CANCELED 0x1
37#define AIO_NOTCANCELED 0x2
38#define AIO_ALLDONE 0x3
39
40/* LIO opcodes */
41#define LIO_NOP 0x0
42#define LIO_WRITE 0x1
43#define LIO_READ 0x2
44
45/* LIO modes */
46#define LIO_NOWAIT 0x0
47#define LIO_WAIT 0x1
48
49/*
50 * Asynchronous I/O structure.
51 * Defined in the Base Definitions volume of IEEE Std 1003.1-2001 .
52 */
53struct aiocb {
54 off_t aio_offset; /* File offset */
55 volatile void *aio_buf; /* I/O buffer in process space */
56 size_t aio_nbytes; /* Length of transfer */
57 int aio_fildes; /* File descriptor */
58 int aio_lio_opcode; /* LIO opcode */
59 int aio_reqprio; /* Request priority offset */
60 struct sigevent aio_sigevent; /* Signal to deliver */
61
62 /* Internal kernel variables */
63 int _state; /* State of the job */
64 int _errno; /* Error value */
65 ssize_t _retval; /* Return value */
66};
67
68/* Internal kernel data */
69#ifdef _KERNEL
70
71/* Default limits of allowed AIO operations */
72#define AIO_LISTIO_MAX 512
73#define AIO_MAX (AIO_LISTIO_MAX * 16)
74
75#include <sys/condvar.h>
76#include <sys/lwp.h>
77#include <sys/mutex.h>
78#include <sys/pool.h>
79#include <sys/queue.h>
80
81/* Operations (as flags) */
82#define AIO_LIO 0x00
83#define AIO_READ 0x01
84#define AIO_WRITE 0x02
85#define AIO_SYNC 0x04
86#define AIO_DSYNC 0x08
87
88/* Job states */
89#define JOB_NONE 0x0
90#define JOB_WIP 0x1
91#define JOB_DONE 0x2
92
93/* Structure of AIO job */
94struct aio_job {
95 int aio_op; /* Operation code */
96 struct aiocb aiocbp; /* AIO data structure */
97 void *aiocb_uptr; /* User-space pointer for identification of job */
98 TAILQ_ENTRY(aio_job) list;
99 struct lio_req *lio;
100};
101
102/* LIO structure */
103struct lio_req {
104 u_int refcnt; /* Reference counter */
105 struct sigevent sig; /* Signal of lio_listio() calls */
106};
107
108/* Structure of AIO data for process */
109struct aioproc {
110 kmutex_t aio_mtx; /* Protects the entire structure */
111 kcondvar_t aio_worker_cv; /* Signals on a new job */
112 kcondvar_t done_cv; /* Signals when the job is done */
113 struct aio_job *curjob; /* Currently processing AIO job */
114 unsigned int jobs_count; /* Count of the jobs */
115 TAILQ_HEAD(, aio_job) jobs_queue;/* Queue of the AIO jobs */
116 struct lwp *aio_worker; /* AIO worker thread */
117};
118
119extern u_int aio_listio_max;
120/* Prototypes */
121void aio_print_jobs(void (*)(const char *, ...) __printflike(1, 2));
122int aio_suspend1(struct lwp *, struct aiocb **, int, struct timespec *);
123
124#endif /* _KERNEL */
125
126#endif /* _SYS_AIO_H_ */