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erofs(5) — Linux manual page

NAME | DESCRIPTION | VERSIONS | CONFIGURATION | SEE ALSO | COLOPHON 

erofs(5)                   File Formats Manual                  erofs(5)

NAME         top

       erofs - the Enhanced Read-Only File System

DESCRIPTION         top

       erofs is a create-once read-only filesystem, with support for
       compression and a multi-device backing store.

       There are two inode formats:

       •  32-byte compact with 16-bit UID/GID, 32-bit file size, and no
          file times
       •  64-byte extended with 32-bit UID/GID, 64-bit file size, and a
          modification time (st_mtim).

   Mount options
       user_xattr
       nouser_xattr
              Controls whether user extended attributes are exposed.
              Defaults to yes.

       acl
       noacl  Controls whether POSIX acl(5)s are exposed.  Defaults to
              yes.

       cache_strategy=disabled|readahead|readaround
              Cache allocation for compressed files: never, if reading
              from start of file, regardless of position.  Defaults to
              readaround.

       dax
       dax=always|never
              Direct Access control.  If always and the source device
              supports DAX, uncompressed non-inlined files will be read
              directly, without going through the page cache.  dax is a
              synonym for always.  Defaults to unset, which is
              equivalent to never.

       device=blobdev
              Add extra device holding some of the data.  Must be given
              as many times and in the same order as --blobdev was to
              mkfs.erofs(1).

       domain_id=did
       fsid=id
              Control CacheFiles on-demand read support.  To be
              documented.

VERSIONS         top

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

CONFIGURATION         top

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

SEE ALSO         top

       mkfs.erofs(1), fsck.erofs(1), dump.erofs(1)

       Documentation/filesystems/erofs.txt in the Linux source.

COLOPHON         top

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Linux man-pages 6.9.1          2024-05-02                       erofs(5)

Pages that refer to this page: filesystems(5)

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