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diff --git a/share/man/man4/ch.4 b/share/man/man4/ch.4 new file mode 100644 index 0000000..d097d54 --- /dev/null +++ b/share/man/man4/ch.4 @@ -0,0 +1,352 @@ +.\" $FreeBSD$ +.\" Copyright (c) 1996 +.\" Julian Elischer <julian@FreeBSD.org>. 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. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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. +.\" +.Dd May 14, 1998 +.Dt CH 4 +.Os +.Sh NAME +.Nm ch +.Nd SCSI media-changer (juke box) driver +.Sh SYNOPSIS +.Cd device ch +.Sh DESCRIPTION +The +.Nm +driver provides support for a +.Em SCSI +media changer. +It allows many slots of media to be multiplexed between +a number of drives. +The changer device may optionally be equipped +with a bar code reader, which reads label information attached to +the media. +.Pp +A SCSI adapter must also be separately configured into the system +before a SCSI changer can be configured. +.Pp +As the SCSI adapter is probed during boot, the +.Em SCSI +bus is scanned for devices. +Any devices found which answer as 'Changer' +type devices will be 'attached' to the +.Nm +driver. +In +.Fx +releases prior to 2.1, the first found will be attached as +.Em ch0 +and the next, +.Em ch1 +etc. +Beginning in 2.1 it is possible to specify what ch unit a device should +come on line as; refer to +.Xr scsi 4 +for details on kernel configuration. +.Sh KERNEL CONFIGURATION +It is only necessary to explicitly configure one +.Nm +device; data structures are dynamically allocated as media changes are found +on the +.Tn SCSI +bus. +.Sh IOCTLS +User mode programs communicate with the changer driver through a +number of ioctls which are described below. +Changer element addresses +used in the communication between the kernel and the changer device are +mapped to zero-based logical addresses. +Element types are specified as follows: +.Bl -tag -width CHET_MT +.It Dv CHET_MT +Medium transport element (picker). +.It Dv CHET_ST +Storage element (slot). +.It Dv CHET_IE +Import/export element (portal). +.It Dv CHET_DT +Data transfer element (drive). +.El +.Pp +The following +.Xr ioctl 2 +calls apply to the changer. +They are defined +in the header file +.In sys/chio.h . +.Bl -tag -width CHIOEXCHANGE +.It Dv CHIOMOVE +.Pq Vt "struct changer_move" +Move a medium from one element to another +.Pq Sy "MOVE MEDIUM" +using the current picker. +The source and destination elements are specified +in a changer_move structure, which includes at least the following +fields: +.Bd -literal -offset indent +u_int cm_fromtype; /* element type to move from */ +u_int cm_fromunit; /* logical unit of from element */ +u_int cm_totype; /* element type to move to */ +u_int cm_tounit; /* logical unit of to element */ +u_int cm_flags; /* misc. flags */ +.Ed +If the +.Dv CM_INVERT +in the +.Va cm_flags +field is set, the medium +changer is instructed to flip the medium while moving it. +.It Dv CHIOEXCHANGE +.Pq Vt "struct changer_exchange" +Move the medium located in the source element to the first destination +element, and move the medium that had been in the first destination +element to the second destination element. +In case of a simple +exchange, the source and second destination elements should be the +same. +The current picker is used to perform the operation. +The addresses of the affected elements is specified to the ioctl in a +.Vt changer_exchange +structure which includes at least the following +fields: +.Bd -literal -offset indent +u_int ce_srctype; /* element type of source */ +u_int ce_srcunit; /* logical unit of source */ +u_int ce_fdsttype; /* element type of first destination */ +u_int ce_fdstunit; /* logical unit of first destination */ +u_int ce_sdsttype; /* element type of second destination */ +u_int ce_sdstunit; /* logical unit of second destination */ +u_int ce_flags; /* misc. flags */ +.Ed +In +.Va ce_flags , +.Dv CM_INVERT1 +and/or +.Dv CM_INVERT2 +may be set +to flip the first or second medium during the exchange operation, +respectively. +.Pp +.Em This operation is untested . +.It Dv CHIOPOSITION +.Pq Vt "struct changer_position" +Position the current picker in front of the specified element. +The element is specified with a changer_position structure, which includes +at least the following elements: +.Bd -literal -offset indent +u_int cp_type; /* element type */ +u_int cp_unit; /* logical unit of element */ +u_int cp_flags; /* misc. flags */ +.Ed +The +.Va cp_flags +field may be set to +.Dv CP_INVERT +to invert the picker during the operation. +.It Dv CHIOGPICKER +.Pq Vt int +Return the logical address of the current picker. +.It Dv CHIOSPICKER +.Pq Vt int +Select the picker specified by the given logical address. +.It Dv CHIOGPARAMS +.Pq Vt "struct changer_params" +Return the configuration parameters for the media changer. +This ioctl +fills the changer_params structure passed by the user with at least the +following fields: +.Bd -literal -offset indent +u_int cp_npickers; /* number of pickers */ +u_int cp_nslots; /* number of slots */ +u_int cp_nportals; /* number of import/export portals */ +u_int cp_ndrives; /* number of drives */ +.Ed +.Pp +This call can be used by applications to query the dimensions of +the jukebox before using the +.Dv CHIGSTATUS +ioctl to query the jukebox status. +.It Dv CHIOIELEM +Perform the +.Sy INITIALIZE ELEMENT STATUS +call on the media changer device. +This forces the media changer to update its internal status +information with respect to loaded media. +It also scans any barcode labels provided that it has a label reader. +The +.Nm +driver's status is not affected by this call. +.It Dv CHIOGSTATUS +.Pq Vt "struct changer_element_status_request" +Perform the +.Sy READ ELEMENT STATUS +call on the media changer device. +This call reads the element status information of the media +changer and converts it to an array of +.Vt changer_element_status +structures. +.Pp +With each call to +.Dv CHIOGSTATUS , +the status of one or more elements of one type may be queried. +.Pp +The application passes a +.Vt changer_element_status_request +structure to the +.Nm +driver which contains the following fields: +.Bd -literal -offset indent +u_int cesr_element_type; +u_int cesr_element_base; +u_int cesr_element_count; +u_int cesr_flags; +struct changer_element_status *cesr_element_status; +.Ed +.Pp +This structure is read by the driver to determine the type, logical +base address and number of elements for which information is to be +returned in the array of +.Vt changer_element_status +structures pointed to by the +.Va cesr_element_status +field. +The application must allocate enough +memory for +.Va cesr_element_count +status structures (see below). +The +.Va cesr_flags +can optionally be set to +.Dv CESR_VOLTAGS +to indicate that volume tag (bar code) information is to be read from +the jukebox and returned. +.Pp +The +.Va cesr_element_base +and +.Va cesr_element_count +fields must be valid with respect to the physical configuration of the changer. +If they are not, the +.Dv CHIOGSTATUS +ioctl returns the +.Er EINVAL +error code. +.Pp +The information about the elements is returned in an array of +.Vt changer_element_status +structures. +This structure include at least the following fields: +.Bd -literal -offset indent +u_int ces_addr; /* element address in media changer */ +u_char ces_flags; /* see CESTATUS definitions below */ +u_char ces_sensecode; /* additional sense code for element */ +u_char ces_sensequal; /* additional sense code qualifier */ +u_char ces_invert; /* invert bit */ +u_char ces_svalid; /* source address (ces_source) valid */ +u_short ces_source; /* source address of medium */ +changer_voltag_t ces_pvoltag; /* primary volume tag */ +changer_voltag_t ces_avoltag; /* alternate volume tag */ +u_char ces_idvalid; /* ces_scsi_id is valid */ +u_char ces_scsi_id; /* SCSI id of element (if ces_idvalid is nonzero) */ +u_char ces_lunvalid; /* ces_scsi_lun is valid */ +u_char ces_scsi_lun; /* SCSI lun of element (if ces_lunvalid is nonzero) */ +.Ed +.Pp +The +.Va ces_addr +field contains the address of the element in the +coordinate system of the media changer. +It is not used by the driver, +and should be used for diagnostic purposes only. +.Pp +The following flags are defined for the +.Va ces_flags +field: +.Bl -tag -width CESTATUS_IMPEXP +.It Dv CESTATUS_FULL +A medium is present. +.It Dv CESTATUS_IMPEXP +The medium has been deposited by the operator (and not by a picker). +.It Dv CESTATUS_EXCEPT +The element is in an exceptional state (e.g.\& invalid barcode label, +barcode not yet scanned). +.It Dv CESTATUS_ACCESS +The element is accessible by the picker. +.It Dv CESTATUS_EXENAB +The element supports medium export. +.It Dv CESTATUS_INENAB +The element supports medium import. +.El +.Pp +Note that not all flags are valid for all element types. +.El +.Sh NOTES +This version of the +.Nm +driver has been tested with a DEC TZ875 (5 slot, one DLT drive) +and a Breece Hill Q47 (60 slot, four DLT drives, barcode reader). +.Pp +Many of the features the +.Nm +driver supports are not thoroughly tested due to the fact that the +devices available for testing do not support the necessary commands. +This is true for alternate volume tags, media flipping, import/export +element handling, multiple picker operation and other things. +.Sh FILES +.Bl -tag -width /dev/ch[0-9] -compact +.It Pa /dev/ch[0-9] +device entries +.El +.Sh DIAGNOSTICS +If the media changer does not support features requested by the +.Nm +driver, it will produce both console error messages and failure return +codes to the ioctls described here. +.Sh SEE ALSO +.Xr cam 4 , +.Xr chio 1 , +.Xr cd 4 , +.Xr da 4 , +.Xr sa 4 +.Sh HISTORY +The +.Nm +driver appeared in +.Bx 386 0.1 . +.Sh AUTHORS +.An -nosplit +The +.Nm +driver was written by +.An Jason R. Thorpe Aq thorpej@and.com +for And Communications, +.Pa http://www.and.com/ . +It was added to the system by +.An Stefan Grefen Aq grefen@goofy.zdv.uni-mainz.de +who apparently had such a device. +It was ported to CAM by +.An Kenneth Merry Aq ken@FreeBSD.org . +It was updated to support volume tags by +.An Hans Huebner Aq hans@artcom.de . |
