1.\" $OpenBSD: bio_register.9,v 1.6 2015/09/14 12:05:33 schwarze Exp $ 2.\" 3.\" Copyright (c) 2006 David Gwynne <dlg@openbsd.org> 4.\" 5.\" Permission to use, copy, modify, and distribute this software for any 6.\" purpose with or without fee is hereby granted, provided that the above 7.\" copyright notice and this permission notice appear in all copies. 8.\" 9.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16.\" 17.Dd $Mdocdate: September 14 2015 $ 18.Dt BIO_REGISTER 9 19.Os 20.Sh NAME 21.Nm bio_register , 22.Nm bio_unregister 23.Nd block I/O ioctl tunnelling interface 24.Sh SYNOPSIS 25.In dev/biovar.h 26.Ft int 27.Fn bio_register "struct device *dev" "int (*bioctl)(struct device *, u_long, caddr_t)" 28.Ft void 29.Fn bio_unregister "struct device *dev" 30.Sh DESCRIPTION 31The block I/O ioctl tunnelling interface is used by drivers to register and 32unregister ioctl handlers to be accessed via the 33.Xr bio 4 34device. 35.Pp 36.Fn bio_register 37is called by the driver represented by 38.Fa dev 39to register the 40.Fa bioctl 41argument as the ioctl handler for itself. 42.Pp 43.Fn bio_unregister 44is called to remove the ioctl handler previously registered with 45.Fn bio_register 46for the device represented by 47.Fa dev . 48.Pp 49.Fn bio_register 50and 51.Fn bio_unregister 52can be called during 53.Xr autoconf 9 54or from process context. 55The 56.Fa bioctl 57callback is called from process context. 58.Sh SEE ALSO 59.Xr bio 4 , 60.Xr autoconf 9 61.Sh HISTORY 62The block I/O ioctl tunnelling interface first appeared in 63.Ox 3.2 . 64.Sh AUTHORS 65The block I/O ioctl tunnelling interface was written by 66.An Niklas Hallqvist Aq Mt niklas@openbsd.org . 67