1.\" 2.\" Copyright (c) 1998 Kenneth D. Merry. 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 3. The name of the author may not be used to endorse or promote products 14.\" derived from this software without specific prior written permission. 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.\" $FreeBSD: src/share/man/man4/xpt.4,v 1.3.2.7 2001/08/17 13:08:40 ru Exp $ 29.\" $DragonFly: src/share/man/man4/xpt.4,v 1.2 2003/06/17 04:36:59 dillon Exp $ 30.\" 31.Dd October 10, 1998 32.Dt XPT 4 33.Os 34.Sh NAME 35.Nm xpt 36.Nd CAM transport layer interface 37.Sh SYNOPSIS 38None. 39.Sh DESCRIPTION 40The 41.Nm 42driver provides a way for userland applications to issue certain CAM CCBs 43to the kernel. 44.Pp 45Since the 46.Nm 47driver allows direct access to the CAM subsystem, system administrators 48should exercise caution when granting access to this driver. If used 49improperly, this driver can allow userland applications to crash a machine 50or cause data loss. 51.Sh KERNEL CONFIGURATION 52There is no kernel configuration required for the 53.Nm 54driver. It is enabled when 55.Tn SCSI 56support is enabled in the kernel. There is one instance of the xpt driver 57per CAM transport layer instance. Since there is currently only one CAM 58transport layer, there will only be one instance of this driver. 59.Sh IOCTLS 60.Bl -tag -width 01234567890123 61.It CAMIOCOMMAND 62This ioctl takes certain kinds of CAM CCBs and passes them through to the 63CAM transport layer for action. Only the following CCB types are 64supported: 65.Pp 66.Bl -tag -width XPT_DEV_MATCH -compact 67.It XPT_SCAN_BUS 68.It XPT_RESET_BUS 69.It XPT_SCAN_LUN 70.It XPT_ENG_INQ 71.It XPT_ENG_EXEC 72.It XPT_DEBUG 73.It XPT_DEV_MATCH 74.It XPT_PATH_INQ 75.El 76.Pp 77The above CCBs are the only ones supported since it makes more sense to 78send them through a generic passthrough device rather than a passthrough 79device tied to a particular underlying 80.Tn SCSI 81device. 82.It CAMGETPASSTHRU 83This ioctl takes an XPT_GDEVLIST CCB, and returns the passthrough device 84corresponding to the device in question. 85.El 86.Sh FILES 87.Bl -tag -width /dev/xpt0 -compact 88.It Pa /dev/xpt0 89Character device node for the 90.Nm 91driver. 92.El 93.Sh DIAGNOSTICS 94None. 95.Sh SEE ALSO 96.Xr cam 3 , 97.Xr cam_cdbparse 3 , 98.Xr pass 4 , 99.Xr camcontrol 8 100.Sh HISTORY 101The CAM transport layer driver first appeared in 102.Fx 3.0 . 103.Sh AUTHORS 104.An Kenneth Merry Aq ken@FreeBSD.org 105