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      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  */
     53 struct 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 */
     94 struct 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 */
    103 struct 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 */
    109 struct 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 
    119 extern u_int aio_listio_max;
    120 /* Prototypes */
    121 void	aio_print_jobs(void (*)(const char *, ...) __printflike(1, 2));
    122 int	aio_suspend1(struct lwp *, struct aiocb **, int, struct timespec *);
    123 
    124 #endif /* _KERNEL */
    125 
    126 #endif /* _SYS_AIO_H_ */
    127