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---------------
* storage/posix
---------------

- SET_FS_ID

  This is so that all filesystem checks are done with the user's
  uid/gid and not GlusterFS's uid/gid.

- MAKE_REAL_PATH

  This macro concatenates the base directory of the posix volume
  ('option directory') with the given path.

- need_xattr in lookup

  If this flag is passed, lookup returns a xattr dictionary that contains
  the file's create time, the file's contents, and the version number
  of the file.

  This is a hack to increase small file performance. If an application
  wants to read a small file, it can finish its job with just a lookup
  call instead of a lookup followed by read.

- getdents/setdents

  These are used by unify to set and get directory entries.

- ALIGN_BUF

  Macro to align an address to a page boundary (4K).

- priv->export_statfs

  In some cases, two exported volumes may reside on the same
  partition on the server. Sending statvfs info for both
  the volumes will lead to erroneous df output at the client,
  since free space on the partition will be counted twice.

  In such cases, user can disable exporting statvfs info
  on one of the volumes by setting this option.

- xattrop

  This fop is used by replicate to set version numbers on files.

- getxattr/setxattr hack to read/write files

  A key, GLUSTERFS_FILE_CONTENT_STRING, is handled in a special way by
  getxattr/setxattr. A getxattr with the key will return the entire
  content of the file as the value. A setxattr with the key will write
  the value as the entire content of the file.

- posix_checksum

  This calculates a simple XOR checksum on all entry names in a
  directory that is used by unify to compare directory contents.