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b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
1da177e4 LT |
2 | /* |
3 | The compile-time configurable defaults for the Linux SCSI tape driver. | |
4 | ||
5 | Copyright 1995-2003 Kai Makisara. | |
6 | ||
40f6b36c | 7 | Last modified: Thu Feb 21 21:47:07 2008 by kai.makisara |
1da177e4 LT |
8 | */ |
9 | ||
10 | #ifndef _ST_OPTIONS_H | |
11 | #define _ST_OPTIONS_H | |
12 | ||
13 | /* If TRY_DIRECT_IO is non-zero, the driver tries to transfer data directly | |
14 | between the user buffer and tape drive. If this is not possible, driver | |
15 | buffer is used. If TRY_DIRECT_IO is zero, driver buffer is always used. */ | |
16 | #define TRY_DIRECT_IO 1 | |
17 | ||
18 | /* The driver does not wait for some operations to finish before returning | |
19 | to the user program if ST_NOWAIT is non-zero. This helps if the SCSI | |
20 | adapter does not support multiple outstanding commands. However, the user | |
21 | should not give a new tape command before the previous one has finished. */ | |
22 | #define ST_NOWAIT 0 | |
23 | ||
24 | /* If ST_IN_FILE_POS is nonzero, the driver positions the tape after the | |
25 | record been read by the user program even if the tape has moved further | |
26 | because of buffered reads. Should be set to zero to support also drives | |
27 | that can't space backwards over records. NOTE: The tape will be | |
28 | spaced backwards over an "accidentally" crossed filemark in any case. */ | |
29 | #define ST_IN_FILE_POS 0 | |
30 | ||
31 | /* If ST_RECOVERED_WRITE_FATAL is non-zero, recovered errors while writing | |
32 | are considered "hard errors". */ | |
33 | #define ST_RECOVERED_WRITE_FATAL 0 | |
34 | ||
35 | /* The "guess" for the block size for devices that don't support MODE | |
36 | SENSE. */ | |
37 | #define ST_DEFAULT_BLOCK 0 | |
38 | ||
39 | /* The minimum tape driver buffer size in kilobytes in fixed block mode. | |
40 | Must be non-zero. */ | |
41 | #define ST_FIXED_BUFFER_BLOCKS 32 | |
42 | ||
43 | /* Maximum number of scatter/gather segments */ | |
44 | #define ST_MAX_SG 256 | |
45 | ||
46 | /* The number of scatter/gather segments to allocate at first try (must be | |
47 | smaller or equal to the maximum). */ | |
48 | #define ST_FIRST_SG 8 | |
49 | ||
50 | /* The size of the first scatter/gather segments (determines the maximum block | |
51 | size for SCSI adapters not supporting scatter/gather). The default is set | |
52 | to try to allocate the buffer as one chunk. */ | |
53 | #define ST_FIRST_ORDER 5 | |
54 | ||
55 | ||
56 | /* The following lines define defaults for properties that can be set | |
57 | separately for each drive using the MTSTOPTIONS ioctl. */ | |
58 | ||
59 | /* If ST_TWO_FM is non-zero, the driver writes two filemarks after a | |
60 | file being written. Some drives can't handle two filemarks at the | |
61 | end of data. */ | |
62 | #define ST_TWO_FM 0 | |
63 | ||
64 | /* If ST_BUFFER_WRITES is non-zero, writes in fixed block mode are | |
65 | buffered until the driver buffer is full or asynchronous write is | |
66 | triggered. May make detection of End-Of-Medium early enough fail. */ | |
67 | #define ST_BUFFER_WRITES 1 | |
68 | ||
69 | /* If ST_ASYNC_WRITES is non-zero, the SCSI write command may be started | |
70 | without waiting for it to finish. May cause problems in multiple | |
71 | tape backups. */ | |
72 | #define ST_ASYNC_WRITES 1 | |
73 | ||
74 | /* If ST_READ_AHEAD is non-zero, blocks are read ahead in fixed block | |
75 | mode. */ | |
76 | #define ST_READ_AHEAD 1 | |
77 | ||
78 | /* If ST_AUTO_LOCK is non-zero, the drive door is locked at the first | |
79 | read or write command after the device is opened. The door is opened | |
80 | when the device is closed. */ | |
81 | #define ST_AUTO_LOCK 0 | |
82 | ||
83 | /* If ST_FAST_MTEOM is non-zero, the MTEOM ioctl is done using the | |
84 | direct SCSI command. The file number status is lost but this method | |
85 | is fast with some drives. Otherwise MTEOM is done by spacing over | |
86 | files and the file number status is retained. */ | |
87 | #define ST_FAST_MTEOM 0 | |
88 | ||
89 | /* If ST_SCSI2LOGICAL is nonzero, the logical block addresses are used for | |
90 | MTIOCPOS and MTSEEK by default. Vendor addresses are used if ST_SCSI2LOGICAL | |
91 | is zero. */ | |
92 | #define ST_SCSI2LOGICAL 0 | |
93 | ||
94 | /* If ST_SYSV is non-zero, the tape behaves according to the SYS V semantics. | |
95 | The default is BSD semantics. */ | |
96 | #define ST_SYSV 0 | |
97 | ||
40f6b36c KM |
98 | /* If ST_SILI is non-zero, the SILI bit is set when reading in variable block |
99 | mode and the block size is determined using the residual returned by the HBA. */ | |
100 | #define ST_SILI 0 | |
101 | ||
1da177e4 LT |
102 | /* Time to wait for the drive to become ready if blocking open */ |
103 | #define ST_BLOCK_SECONDS 120 | |
104 | ||
105 | #endif |