Merge tag 'ceph-for-5.19-rc7' of https://github.com/ceph/ceph-client
[linux-block.git] / Documentation / admin-guide / jfs.rst
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1da177e4 2IBM's Journaled File System (JFS) for Linux
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4
5JFS Homepage: http://jfs.sourceforge.net/
6
7The following mount options are supported:
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b40c2e66 9(*) == default
1da177e4 10
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11iocharset=name
12 Character set to use for converting from Unicode to
1da177e4 13 ASCII. The default is to do no conversion. Use
4de151d8 14 iocharset=utf8 for UTF-8 translations. This requires
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15 CONFIG_NLS_UTF8 to be set in the kernel .config file.
16 iocharset=none specifies the default behavior explicitly.
17
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18resize=value
19 Resize the volume to <value> blocks. JFS only supports
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20 growing a volume, not shrinking it. This option is only
21 valid during a remount, when the volume is mounted
22 read-write. The resize keyword with no value will grow
23 the volume to the full size of the partition.
24
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25nointegrity
26 Do not write to the journal. The primary use of this option
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27 is to allow for higher performance when restoring a volume
28 from backup media. The integrity of the volume is not
29 guaranteed if the system abnormally abends.
30
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31integrity(*)
32 Commit metadata changes to the journal. Use this option to
b40c2e66 33 remount a volume where the nointegrity option was
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34 previously specified in order to restore normal behavior.
35
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36errors=continue
37 Keep going on a filesystem error.
38errors=remount-ro(*)
39 Remount the filesystem read-only on an error.
40errors=panic
41 Panic and halt the machine if an error occurs.
1da177e4 42
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43uid=value
44 Override on-disk uid with specified value
45gid=value
46 Override on-disk gid with specified value
47umask=value
48 Override on-disk umask with specified octal value. For
49 directories, the execute bit will be set if the corresponding
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50 read bit is set.
51
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52discard=minlen, discard/nodiscard(*)
53 This enables/disables the use of discard/TRIM commands.
54 The discard/TRIM commands are sent to the underlying
55 block device when blocks are freed. This is useful for SSD
56 devices and sparse/thinly-provisioned LUNs. The FITRIM ioctl
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57 command is also available together with the nodiscard option.
58 The value of minlen specifies the minimum blockcount, when
f884ab15 59 a TRIM command to the block device is considered useful.
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60 When no value is given to the discard option, it defaults to
61 64 blocks, which means 256KiB in JFS.
62 The minlen value of discard overrides the minlen value given
63 on an FITRIM ioctl().
64
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65The JFS mailing list can be subscribed to by using the link labeled
66"Mail list Subscribe" at our web page http://jfs.sourceforge.net/