Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages

  
 
  

home | help
MTIO(4)			    Kernel Interfaces Manual		       MTIO(4)

NAME
       mtio -- FreeBSD magtape interface

DESCRIPTION
       The  special  files named /dev/[en]sa* refer to SCSI tape drives, which
       may be attached to the system.  /dev/sa*.ctl are	control	 devices  that
       can  be	used to	issue ioctls to	the SCSI tape driver to	set parameters
       that are	required to last beyond	the unmounting of a tape.

       The rewind devices automatically	rewind when the	last  requested	 read,
       write  or  seek	has finished, or the end of the	tape has been reached.
       The letter `n' is prepended to the name of the no-rewind	devices.   The
       letter `e' is prepended to the name of the eject	devices.

       Tapes  can  be  written	with  either  fixed length records or variable
       length records.	See sa(4) for more information.	  Two  filemarks  mark
       the  end	 of a tape, and	one filemark marks the end of a	tape file.  If
       the tape	is not to be rewound it	is positioned with the head in between
       the two tape marks, where the next write	will  over  write  the	second
       end-of-file marker.

       All of the magtape devices may be manipulated with the mt(1) command.

       A  number  of  ioctl(2)	operations are available on raw	magnetic tape.
       The following definitions are from <sys/mtio.h>:

       #ifndef _SYS_MTIO_H_
       #define _SYS_MTIO_H_

       #ifndef _KERNEL
       #include	<sys/types.h>
       #endif
       #include	<sys/ioccom.h>

       /*
	* Structures and definitions for mag tape io control commands
	*/

       /* structure for	MTIOCTOP - mag tape op command */
       struct mtop {
	       short   mt_op;	       /* operations defined below */
	       int32_t mt_count;       /* how many of them */
       };

       /* operations */
       #define MTWEOF	       0       /* write	an end-of-file record */
       #define MTFSF	       1       /* forward space	file */
       #define MTBSF	       2       /* backward space file */
       #define MTFSR	       3       /* forward space	record */
       #define MTBSR	       4       /* backward space record	*/
       #define MTREW	       5       /* rewind */
       #define MTOFFL	       6       /* rewind and put the drive offline */
       #define MTNOP	       7       /* no operation,	sets status only */
       #define MTCACHE	       8       /* enable controller cache */
       #define MTNOCACHE       9       /* disable controller cache */

       #if defined(__FreeBSD__)
       /* Set block size for device. If	device is a variable size dev	       */
       /* a non	zero parameter will change the device to a fixed block size    */
       /* device with block size set to	that of	the parameter passed in.       */
       /* Resetting the	block size to 0	will restore the device	to a variable  */
       /* block	size device. */

       #define MTSETBSIZ       10

       /* Set density values for device. Sets the value	for the	opened mode only. */

       #define MTSETDNSTY      11

       #define MTERASE	       12      /* erase	to EOM */
       #define MTEOD	       13      /* Space	to EOM */
       #define MTCOMP	       14      /* select compression mode 0=off, 1=def */
       #define MTRETENS	       15      /* re-tension tape */
       #define MTWSS	       16      /* write	setmark(s) */
       #define MTFSS	       17      /* forward space	setmark	*/
       #define MTBSS	       18      /* backward space setmark */
       #define MTLOAD	       19      /* load tape in drive */
       #define MTWEOFI	       20      /* write	an end-of-file record without waiting*/

       #define MT_COMP_ENABLE	       0xffffffff
       #define MT_COMP_DISABLED	       0xfffffffe
       #define MT_COMP_UNSUPP	       0xfffffffd

       /*
	* Values in mt_dsreg that say what the device is doing
	*/
       #define MTIO_DSREG_NIL  0       /* Unknown */
       #define MTIO_DSREG_REST 1       /* Doing	Nothing	*/
       #define MTIO_DSREG_RBSY 2       /* Communicating	with tape (but no motion) */
       #define MTIO_DSREG_WR   20      /* Writing */
       #define MTIO_DSREG_FMK  21      /* Writing Filemarks */
       #define MTIO_DSREG_ZER  22      /* Erasing */
       #define MTIO_DSREG_RD   30      /* Reading */
       #define MTIO_DSREG_FWD  40      /* Spacing Forward */
       #define MTIO_DSREG_REV  41      /* Spacing Reverse */
       #define MTIO_DSREG_POS  42      /* Hardware Positioning (direction unknown) */
       #define MTIO_DSREG_REW  43      /* Rewinding */
       #define MTIO_DSREG_TEN  44      /* Retensioning */
       #define MTIO_DSREG_UNL  45      /* Unloading */
       #define MTIO_DSREG_LD   46      /* Loading */

       #endif  /* __FreeBSD__ */

       /* structure for	MTIOCGET - mag tape get	status command */

       struct mtget {
	       short   mt_type;	       /* type of magtape device */
       /* the following	two registers are grossly device dependent */
	       short   mt_dsreg;       /* ``drive status'' register */
	       short   mt_erreg;       /* ``error'' register */
       /* end device-dependent registers */
	       /*
		* Note that the	residual count,	while maintained, may be
		* be nonsense because the size of the residual may (greatly)
		* exceed 32 K-bytes. Use the MTIOCERRSTAT ioctl	to get a
		* more accurate	count.
		*/
	       short   mt_resid;       /* residual count */
       #if defined (__FreeBSD__)
	       int32_t mt_blksiz;      /* presently operating blocksize	*/
	       int32_t mt_density;     /* presently operating density */
	       uint32_t	mt_comp;       /* presently operating compression */
	       int32_t mt_blksiz0;     /* blocksize for	mode 0 */
	       int32_t mt_blksiz1;     /* blocksize for	mode 1 */
	       int32_t mt_blksiz2;     /* blocksize for	mode 2 */
	       int32_t mt_blksiz3;     /* blocksize for	mode 3 */
	       int32_t mt_density0;    /* density for mode 0 */
	       int32_t mt_density1;    /* density for mode 1 */
	       int32_t mt_density2;    /* density for mode 2 */
	       int32_t mt_density3;    /* density for mode 3 */
       /* the following	are not	yet implemented	*/
	       uint32_t	mt_comp0;      /* compression type for mode 0 */
	       uint32_t	mt_comp1;      /* compression type for mode 1 */
	       uint32_t	mt_comp2;      /* compression type for mode 2 */
	       uint32_t	mt_comp3;      /* compression type for mode 3 */
       /* end not yet implemented */
       #endif
	       int32_t mt_fileno;      /* relative file	number of current position */
	       int32_t mt_blkno;       /* relative block number	of current position */
       };

       /* structure for	MTIOCERRSTAT - tape get	error status command */
       /* really only supported	for SCSI tapes right now */
       struct scsi_tape_errors {
	       /*
		* These	are latched from the last command that had a SCSI
		* Check	Condition noted	for these operations. The act
		* of issuing an	MTIOCERRSTAT unlatches and clears them.
		*/
	       uint8_t io_sense[32];   /* Last Sense Data For Data I/O */
	       int32_t io_resid;       /* residual count from last Data	I/O */
	       uint8_t io_cdb[16];     /* Command that Caused the Last Data Sense */
	       uint8_t ctl_sense[32];  /* Last Sense Data For Control I/O */
	       int32_t ctl_resid;      /* residual count from last Control I/O */
	       uint8_t ctl_cdb[16];    /* Command that Caused the Last Control Sense */
	       /*
		* These	are the	read and write cumulative error	counters.
		* (how to reset	cumulative error counters is not yet defined).
		* (not implemented as yet but space is being reserved for them)
		*/
	       struct {
		       uint32_t	retries;       /* total	# retries performed */
		       uint32_t	corrected;     /* total	# corrections performed	*/
		       uint32_t	processed;     /* total	# corrections successful */
		       uint32_t	failures;      /* total	# corrections/retries failed */
		       uint64_t	nbytes;	       /* total	# bytes	processed */
	       } wterr,	rderr;
       };

       union mterrstat {
	       struct scsi_tape_errors scsi_errstat;
	       char _reserved_padding[256];
       };

       struct mtrblim {
	       uint32_t	granularity;
	       uint32_t	min_block_length;
	       uint32_t	max_block_length;
       };

       typedef enum {
	       MT_LOCATE_DEST_OBJECT   = 0x00,
	       MT_LOCATE_DEST_FILE     = 0x01,
	       MT_LOCATE_DEST_SET      = 0x02,
	       MT_LOCATE_DEST_EOD      = 0x03
       } mt_locate_dest_type;

       typedef enum {
	       MT_LOCATE_BAM_IMPLICIT  = 0x00,
	       MT_LOCATE_BAM_EXPLICIT  = 0x01
       } mt_locate_bam;

       typedef enum {
	       MT_LOCATE_FLAG_IMMED	       = 0x01,
	       MT_LOCATE_FLAG_CHANGE_PART      = 0x02
       } mt_locate_flags;

       struct mtlocate {
	       mt_locate_flags	       flags;
	       mt_locate_dest_type     dest_type;
	       mt_locate_bam	       block_address_mode;
	       int64_t		       partition;
	       uint64_t		       logical_id;
	       uint8_t		       reserved[64];
       };

       typedef enum {
	       MT_EXT_GET_NONE,
	       MT_EXT_GET_OK,
	       MT_EXT_GET_NEED_MORE_SPACE,
	       MT_EXT_GET_ERROR
       } mt_ext_get_status;

       struct mtextget {
	       uint32_t		       alloc_len;
	       char		       *status_xml;
	       uint32_t		       fill_len;
	       mt_ext_get_status       status;
	       char		       error_str[128];
	       uint8_t		       reserved[64];
       };

       #define MT_EXT_GET_ROOT_NAME	       "mtextget"
       #define MT_DENSITY_ROOT_NAME	       "mtdensity"
       #define MT_MEDIA_DENSITY_NAME	       "media_density"
       #define MT_DENSITY_REPORT_NAME	       "density_report"
       #define MT_MEDIUM_TYPE_REPORT_NAME      "medium_type_report"
       #define MT_MEDIA_REPORT_NAME	       "media_report"
       #define MT_DENSITY_ENTRY_NAME	       "density_entry"

       #define MT_DENS_WRITE_OK		       0x80
       #define MT_DENS_DUP		       0x40
       #define MT_DENS_DEFLT		       0x20

       #define MT_PARAM_FIXED_STR_LEN  32
       union mt_param_value {
	       int64_t	       value_signed;
	       uint64_t	       value_unsigned;
	       char	       *value_var_str;
	       char	       value_fixed_str[MT_PARAM_FIXED_STR_LEN];
	       uint8_t	       reserved[64];
       };

       typedef enum {
	       MT_PARAM_SET_NONE,
	       MT_PARAM_SET_SIGNED,
	       MT_PARAM_SET_UNSIGNED,
	       MT_PARAM_SET_VAR_STR,
	       MT_PARAM_SET_FIXED_STR
       } mt_param_set_type;

       typedef enum {
	       MT_PARAM_STATUS_NONE,
	       MT_PARAM_STATUS_OK,
	       MT_PARAM_STATUS_ERROR
       } mt_param_set_status;

       #define MT_PARAM_VALUE_NAME_LEN 64
       struct mtparamset {
	       char		       value_name[MT_PARAM_VALUE_NAME_LEN];
	       mt_param_set_type       value_type;
	       int		       value_len;
	       union mt_param_value    value;
	       mt_param_set_status     status;
	       char		       error_str[128];
       };

       #define MT_PARAM_ROOT_NAME      "mtparamget"
       #define MT_PROTECTION_NAME      "protection"

       /*
	* Set a	list of	parameters.
	*/
       struct mtsetlist	{
	       int num_params;
	       int param_len;
	       struct mtparamset *params;
       };

       /*
	* Constants for	mt_type	byte.  These are the same
	* for controllers compatible with the types listed.
	*/
       #define MT_ISTS	       0x01	       /* TS-11	*/
       #define MT_ISHT	       0x02	       /* TM03 Massbus:	TE16, TU45, TU77 */
       #define MT_ISTM	       0x03	       /* TM11/TE10 Unibus */
       #define MT_ISMT	       0x04	       /* TM78/TU78 Massbus */
       #define MT_ISUT	       0x05	       /* SI TU-45 emulation on	Unibus */
       #define MT_ISCPC	       0x06	       /* SUN */
       #define MT_ISAR	       0x07	       /* SUN */
       #define MT_ISTMSCP      0x08	       /* DEC TMSCP protocol (TU81, TK50) */
       #define MT_ISCY	       0x09	       /* CCI Cipher */
       #define MT_ISCT	       0x0a	       /* HP 1/4 tape */
       #define MT_ISFHP	       0x0b	       /* HP 7980 1/2 tape */
       #define MT_ISEXABYTE    0x0c	       /* Exabyte */
       #define MT_ISEXA8200    0x0c	       /* Exabyte EXB-8200 */
       #define MT_ISEXA8500    0x0d	       /* Exabyte EXB-8500 */
       #define MT_ISVIPER1     0x0e	       /* Archive Viper-150 */
       #define MT_ISPYTHON     0x0f	       /* Archive Python (DAT) */
       #define MT_ISHPDAT      0x10	       /* HP 35450A DAT	drive */
       #define MT_ISMFOUR      0x11	       /* M4 Data 1/2 9track drive */
       #define MT_ISTK50       0x12	       /* DEC SCSI TK50	*/
       #define MT_ISMT02       0x13	       /* Emulex MT02 SCSI tape	controller */

       /* mag tape io control commands */
       #define MTIOCTOP	       _IOW('m', 1, struct mtop)       /* do a mag tape	op */
       #define MTIOCGET	       _IOR('m', 2, struct mtget)      /* get tape status */
       /* these	two do not appear to be	used anywhere */
       #define MTIOCIEOT       _IO('m',	3)		       /* ignore EOT error */
       #define MTIOCEEOT       _IO('m',	4)		       /* enable EOT error */
       /*
	* When more SCSI-3 SSC (streaming device) devices are out there
	* that support the full	32 byte	type 2 structure, we'll	have to
	* rethink these	ioctls to support all the entities they	haul into
	* the picture (64 bit blocks, logical file record numbers, etc..).
	*/
       #define MTIOCRDSPOS     _IOR('m', 5, uint32_t)  /* get logical blk addr */
       #define MTIOCRDHPOS     _IOR('m', 6, uint32_t)  /* get hardware blk addr	*/
       #define MTIOCSLOCATE    _IOW('m', 5, uint32_t)  /* seek to logical blk addr */
       #define MTIOCHLOCATE    _IOW('m', 6, uint32_t)  /* seek to hardware blk addr */
       #define MTIOCERRSTAT    _IOR('m', 7, union mterrstat)   /* get tape errors */
       /*
	* Set EOT model- argument is number of filemarks to end	a tape with.
	* Note that not	all possible values will be accepted.
	*/
       #define MTIOCSETEOTMODEL	       _IOW('m', 8, uint32_t)
       /* Get current EOT model	*/
       #define MTIOCGETEOTMODEL	       _IOR('m', 8, uint32_t)
       #define MTIOCRBLIM      _IOR('m', 9, struct mtrblim)    /* get block limits */
       #define MTIOCEXTLOCATE  _IOW('m', 10, struct mtlocate)  /* seek to position */
       #define MTIOCEXTGET     _IOWR('m', 11, struct mtextget) /* get tape status */
       #define MTIOCPARAMGET   _IOWR('m', 12, struct mtextget) /* get tape params */
       #define MTIOCPARAMSET   _IOWR('m', 13, struct mtparamset) /* set	tape params */
       #define MTIOCSETLIST    _IOWR('m', 14, struct mtsetlist)	/* set N params	*/

       #ifndef _KERNEL
       #define DEFTAPE "/dev/nsa0"
       #endif

       #endif /* !_SYS_MTIO_H_ */

FILES
       /dev/[en]sa*

SEE ALSO
       mt(1), tar(1), sa(4)

HISTORY
       The mtio	manual appeared	in 4.2BSD.  An i386 version first appeared  in
       FreeBSD 2.2.

FreeBSD	14.3		       February	12, 2015		       MTIO(4)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=mtio&sektion=4&manpath=FreeBSD+14.3-RELEASE+and+Ports>

home | help