1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
101 lines
3.7 KiB
C
101 lines
3.7 KiB
C
/*
|
|
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
|