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Diffstat (limited to 'drivers/scsi/st_options.h')
| -rw-r--r-- | drivers/scsi/st_options.h | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/drivers/scsi/st_options.h b/drivers/scsi/st_options.h new file mode 100644 index 000000000000..b6b5c9c37677 --- /dev/null +++ b/drivers/scsi/st_options.h @@ -0,0 +1,100 @@ +/* + The compile-time configurable defaults for the Linux SCSI tape driver. + + Copyright 1995-2003 Kai Makisara. + + Last modified: Mon Apr 7 22:49:18 2003 by makisara +*/ + +#ifndef _ST_OPTIONS_H +#define _ST_OPTIONS_H + +/* If TRY_DIRECT_IO is non-zero, the driver tries to transfer data directly + between the user buffer and tape drive. If this is not possible, driver + buffer is used. If TRY_DIRECT_IO is zero, driver buffer is always used. */ +#define TRY_DIRECT_IO 1 + +/* The driver does not wait for some operations to finish before returning + to the user program if ST_NOWAIT is non-zero. This helps if the SCSI + adapter does not support multiple outstanding commands. However, the user + should not give a new tape command before the previous one has finished. */ +#define ST_NOWAIT 0 + +/* If ST_IN_FILE_POS is nonzero, the driver positions the tape after the + record been read by the user program even if the tape has moved further + because of buffered reads. Should be set to zero to support also drives + that can't space backwards over records. NOTE: The tape will be + spaced backwards over an "accidentally" crossed filemark in any case. */ +#define ST_IN_FILE_POS 0 + +/* If ST_RECOVERED_WRITE_FATAL is non-zero, recovered errors while writing + are considered "hard errors". */ +#define ST_RECOVERED_WRITE_FATAL 0 + +/* The "guess" for the block size for devices that don't support MODE + SENSE. */ +#define ST_DEFAULT_BLOCK 0 + +/* The minimum tape driver buffer size in kilobytes in fixed block mode. + Must be non-zero. */ +#define ST_FIXED_BUFFER_BLOCKS 32 + +/* Maximum number of scatter/gather segments */ +#define ST_MAX_SG 256 + +/* The number of scatter/gather segments to allocate at first try (must be + smaller or equal to the maximum). */ +#define ST_FIRST_SG 8 + +/* The size of the first scatter/gather segments (determines the maximum block + size for SCSI adapters not supporting scatter/gather). The default is set + to try to allocate the buffer as one chunk. */ +#define ST_FIRST_ORDER 5 + + +/* The following lines define defaults for properties that can be set + separately for each drive using the MTSTOPTIONS ioctl. */ + +/* If ST_TWO_FM is non-zero, the driver writes two filemarks after a + file being written. Some drives can't handle two filemarks at the + end of data. */ +#define ST_TWO_FM 0 + +/* If ST_BUFFER_WRITES is non-zero, writes in fixed block mode are + buffered until the driver buffer is full or asynchronous write is + triggered. May make detection of End-Of-Medium early enough fail. */ +#define ST_BUFFER_WRITES 1 + +/* If ST_ASYNC_WRITES is non-zero, the SCSI write command may be started + without waiting for it to finish. May cause problems in multiple + tape backups. */ +#define ST_ASYNC_WRITES 1 + +/* If ST_READ_AHEAD is non-zero, blocks are read ahead in fixed block + mode. */ +#define ST_READ_AHEAD 1 + +/* If ST_AUTO_LOCK is non-zero, the drive door is locked at the first + read or write command after the device is opened. The door is opened + when the device is closed. */ +#define ST_AUTO_LOCK 0 + +/* If ST_FAST_MTEOM is non-zero, the MTEOM ioctl is done using the + direct SCSI command. The file number status is lost but this method + is fast with some drives. Otherwise MTEOM is done by spacing over + files and the file number status is retained. */ +#define ST_FAST_MTEOM 0 + +/* If ST_SCSI2LOGICAL is nonzero, the logical block addresses are used for + MTIOCPOS and MTSEEK by default. Vendor addresses are used if ST_SCSI2LOGICAL + is zero. */ +#define ST_SCSI2LOGICAL 0 + +/* If ST_SYSV is non-zero, the tape behaves according to the SYS V semantics. + The default is BSD semantics. */ +#define ST_SYSV 0 + +/* Time to wait for the drive to become ready if blocking open */ +#define ST_BLOCK_SECONDS 120 + +#endif |