NAME

       erofs - the Enhanced Read-Only File System

DESCRIPTION

       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

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

CONFIGURATION

       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

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

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