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Diffstat (limited to 'share/man/man4/targ.4')
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diff --git a/share/man/man4/targ.4 b/share/man/man4/targ.4 new file mode 100644 index 0000000..6c61735 --- /dev/null +++ b/share/man/man4/targ.4 @@ -0,0 +1,152 @@ +.\" Copyright (c) 2002 +.\" Nate Lawson. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Neither the name of the author nor the names of any co-contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY Nate Lawson AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd December 13, 2011 +.Dt TARG 4 +.Os +.Sh NAME +.Nm targ +.Nd SCSI target emulator driver +.Sh SYNOPSIS +To compile this driver into the kernel, +place the following line in your +kernel configuration file: +.Bd -ragged -offset indent +.Cd "device targ" +.Ed +.Sh DESCRIPTION +The +.Nm +driver provides an interface for usermode programs to emulate SCSI target +devices. +A sample program that emulates a disk drive (similar to +.Xr da 4 ) +can be found in +.Pa /usr/share/examples/scsi_target . +.Pp +The +.Nm +driver supplies the control device +.Pa /dev/targ . +After opening the device, the file descriptor must be bound to a +specific bus/target/LUN and enabled to process CCBs using the +.Dv TARGIOCENABLE +ioctl. +The process then uses +.Xr write 2 +to send CCBs to the SIM and +.Xr poll 2 +or +.Xr kqueue 2 +to see if responses are ready. +Pointers to completed CCBs are returned via +.Xr read 2 . +Any data transfers requested by the user CCBs are done via zero-copy IO. +.Sh IOCTLS +The following +.Xr ioctl 2 +calls are defined in the header file +.In cam/scsi/scsi_targetio.h . +.Bl -tag -width ".Dv TARGIOCDISABLE" +.It Dv TARGIOCENABLE +.Pq Vt "struct ioc_enable_lun" +Enable target mode on the LUN specified by the following structure: +.Bd -literal -offset indent +struct ioc_enable_lun { + path_id_t path_id; + target_id_t target_id; + lun_id_t lun_id; + int grp6_len; + int grp7_len; +}; +.Ed +.Pp +The selected path (bus), target, and LUN must not already be in use or +.Er EADDRINUSE +is returned. +If +.Va grp6_len +or +.Va grp7_len +are non-zero, reception of vendor-specific commands +is enabled. +.It Dv TARGIOCDISABLE +Disable target mode and abort all pending CCBs. +The CCBs may optionally be read as they complete. +.Dv TARGIOCENABLE +can then be called to activate a different LUN. +Multiple disable calls have no effect. +The +.Xr close 2 +system call automatically disables target mode if enabled. +.It Dv TARGIOCDEBUG +.Pq Vt int +Enables +.Dv CAM_PERIPH +debugging if the argument is non-zero, otherwise disables +it. +.El +.Sh FILES +.Bl -tag -width ".Pa /sys/cam/scsi/scsi_target.c" -compact +.It In cam/scsi/scsi_targetio.h +describes the usermode interface. +.It Pa /sys/cam/scsi/scsi_target.c +is the driver source file. +.It Pa /dev/targ +is the control device. +.El +.Sh SEE ALSO +.Pa /usr/share/examples/scsi_target , +.Xr ahc 4 , +.Xr isp 4 , +.Xr scsi 4 +.Rs +.%T "FreeBSD Target Information" +.%U http://www.root.org/~nate/freebsd/ +.Re +.Sh AUTHORS +.An -nosplit +The +.Nm +driver first appeared in +.Fx 3.0 +and was written by +.An Justin T. Gibbs . +It was rewritten +for +.Fx 5.0 +by +.An Nate Lawson Aq nate@root.org . +.Sh BUGS +Currently, only the +.Xr ahc 4 +and +.Xr isp 4 +drivers fully support target mode. +.Pp +The +.Xr ahc 4 +driver does not support tagged queuing in target mode. |
