1erofs(5)                      File Formats Manual                     erofs(5)
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NAME

6       erofs - the Enhanced Read-Only File System
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DESCRIPTION

9       erofs  is a create-once read-only filesystem, with support for compres‐
10       sion and a multi-device backing store.
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12       There are two inode formats:
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14       •  32-byte compact with 16-bit UID/GID, 32-bit file size, and  no  file
15          times
16       •  64-byte  extended with 32-bit UID/GID, 64-bit file size, and a modi‐
17          fication time (st_mtim).
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19   Mount options
20       user_xattr
21       nouser_xattr
22              Controls whether user extended attributes are exposed.  Defaults
23              to yes.
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25       acl
26       noacl  Controls whether POSIX acl(5)s are exposed.  Defaults to yes.
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28       cache_strategy=disabled|readahead|readaround
29              Cache  allocation  for  compressed files: never, if reading from
30              start of file, regardless of position.  Defaults to readaround.
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32       dax
33       dax=always|never
34              Direct Access control.  If always and the source device supports
35              DAX, uncompressed non-inlined files will be read directly, with‐
36              out going through the page cache.  dax is a synonym for  always.
37              Defaults to unset, which is equivalent to never.
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39       device=blobdev
40              Add  extra  device  holding  some of the data.  Must be given as
41              many  times  and  in  the  same  order  as  --blobdev   was   to
42              mkfs.erofs(1).
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44       domain_id=did
45       fsid=id
46              Control CacheFiles on-demand read support.  To be documented.
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VERSIONS

49       erofs  images are versioned through the use of feature flags; these are
50       listed in the -E section of mkfs.erofs(1),
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CONFIGURATION

53       Linux must be configured with the CONFIG_EROFS_FS option to mount EROFS
54       filesystems.   There  are  sub-configuration  items  that  restrict the
55       availability of some of the parameters above.
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SEE ALSO

58       mkfs.erofs(1), fsck.erofs(1), dump.erofs(1)
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60       Documentation/filesystems/erofs.txt in the Linux source.
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64Linux man-pages 6.05              2023-04-29                          erofs(5)
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