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.Dd October 10, 1998 29.Dt XPT 4 30.Os 31.Sh NAME 32.Nm xpt 33.Nd CAM transport layer interface 34.Sh SYNOPSIS 35None. 36.Sh DESCRIPTION 37The 38.Nm 39driver provides a way for userland applications to issue certain CAM CCBs 40to the kernel. 41.Pp 42Since the 43.Nm 44driver allows direct access to the CAM subsystem, system administrators 45should exercise caution when granting access to this driver. 46If used 47improperly, this driver can allow userland applications to crash a machine 48or cause data loss. 49.Sh KERNEL CONFIGURATION 50There is no kernel configuration required for the 51.Nm 52driver. 53It is enabled when 54.Tn SCSI 55support is enabled in the kernel. 56There is one instance of the xpt driver 57per CAM transport layer instance. 58Since there is currently only one CAM 59transport layer, there will only be one instance of this driver. 60.Sh IOCTLS 61.Bl -tag -width 01234567890123 62.It CAMIOCOMMAND 63This ioctl takes certain kinds of CAM CCBs and passes them through to the 64CAM transport layer for action. 65Only the following CCB types are 66supported: 67.Pp 68.Bl -tag -width XPT_DEV_MATCH -compact 69.It XPT_SCAN_BUS 70.It XPT_RESET_BUS 71.It XPT_SCAN_LUN 72.It XPT_ENG_INQ 73.It XPT_ENG_EXEC 74.It XPT_DEBUG 75.It XPT_DEV_MATCH 76.It XPT_PATH_INQ 77.El 78.Pp 79The above CCBs are the only ones supported since it makes more sense to 80send them through a generic passthrough device rather than a passthrough 81device tied to a particular underlying 82.Tn SCSI 83device. 84.It CAMGETPASSTHRU 85This ioctl takes an XPT_GDEVLIST CCB, and returns the passthrough device 86corresponding to the device in question. 87.El 88.Sh FILES 89.Bl -tag -width /dev/xpt0 -compact 90.It Pa /dev/xpt0 91Character device node for the 92.Nm 93driver. 94.El 95.Sh DIAGNOSTICS 96None. 97.Sh SEE ALSO 98.Xr cam 3 , 99.Xr cam_cdbparse 3 , 100.Xr pass 4 , 101.Xr camcontrol 8 102.Sh HISTORY 103The CAM transport layer driver first appeared in 104.Fx 3.0 . 105.Sh AUTHORS 106.An Kenneth Merry Aq Mt ken@FreeBSD.org 107