1.\" -*- nroff -*- 2.\" 3.\" Copyright (c) 1996 Doug Rabson 4.\" 5.\" All rights reserved. 6.\" 7.\" This program is free software. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 19.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 22.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28.\" 29.\" $FreeBSD$ 30.\" 31.Dd February 2, 2014 32.Dt VOP_STRATEGY 9 33.Os 34.Sh NAME 35.Nm VOP_STRATEGY 36.Nd read or write a file system buffer 37.Sh SYNOPSIS 38.In sys/param.h 39.In sys/vnode.h 40.Ft int 41.Fn VOP_STRATEGY "struct vnode *vp" "struct buf *bp" 42.Sh DESCRIPTION 43The arguments are: 44.Bl -tag -width 2n 45.It Fa vp 46The vnode that the buffer is for. 47.It Fa bp 48The buffer to be read or written. 49.El 50.Pp 51This call either reads or writes data from a file, depending on the value of 52.Fa bp->b_io.bio_cmd . 53.Pp 54The call may block. 55.Sh RETURN VALUES 56Always zero. 57Errors should be signalled by setting BIO_ERROR on b_ioflags field in struct buf, 58and setting b_error to the appropriate errno value. 59.Sh SEE ALSO 60.Xr buf 9 , 61.Xr vnode 9 62.Sh AUTHORS 63This manual page was written by 64.An Doug Rabson . 65