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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.
+
+