Linux-libre 4.2-gnu

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diff --git a/Documentation/filesystems/aufs/design/04branch.txt b/Documentation/filesystems/aufs/design/04branch.txt
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--- a/Documentation/filesystems/aufs/design/04branch.txt
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-
-# Copyright (C) 2005-2015 Junjiro R. Okajima
-# 
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 2 of the License, or
-# (at your option) any later version.
-# 
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-# 
-# You should have received a copy of the GNU General Public License
-# along with this program.  If not, see <http://www.gnu.org/licenses/>.
-
-Branch Manipulation
-
-Since aufs supports dynamic branch manipulation, ie. add/remove a branch
-and changing its permission/attribute, there are a lot of works to do.
-
-
-Add a Branch
-----------------------------------------------------------------------
-o Confirm the adding dir exists outside of aufs, including loopback
-  mount, and its various attributes.
-o Initialize the xino file and whiteout bases if necessary.
-  See struct.txt.
-
-o Check the owner/group/mode of the directory
-  When the owner/group/mode of the adding directory differs from the
-  existing branch, aufs issues a warning because it may impose a
-  security risk.
-  For example, when a upper writable branch has a world writable empty
-  top directory, a malicious user can create any files on the writable
-  branch directly, like copy-up and modify manually. If something like
-  /etc/{passwd,shadow} exists on the lower readonly branch but the upper
-  writable branch, and the writable branch is world-writable, then a
-  malicious guy may create /etc/passwd on the writable branch directly
-  and the infected file will be valid in aufs.
-  I am afraid it can be a security issue, but aufs can do nothing except
-  producing a warning.
-
-
-Delete a Branch
-----------------------------------------------------------------------
-o Confirm the deleting branch is not busy
-  To be general, there is one merit to adopt "remount" interface to
-  manipulate branches. It is to discard caches. At deleting a branch,
-  aufs checks the still cached (and connected) dentries and inodes. If
-  there are any, then they are all in-use. An inode without its
-  corresponding dentry can be alive alone (for example, inotify/fsnotify case).
-
-  For the cached one, aufs checks whether the same named entry exists on
-  other branches.
-  If the cached one is a directory, because aufs provides a merged view
-  to users, as long as one dir is left on any branch aufs can show the
-  dir to users. In this case, the branch can be removed from aufs.
-  Otherwise aufs rejects deleting the branch.
-
-  If any file on the deleting branch is opened by aufs, then aufs
-  rejects deleting.
-
-
-Modify the Permission of a Branch
-----------------------------------------------------------------------
-o Re-initialize or remove the xino file and whiteout bases if necessary.
-  See struct.txt.
-
-o rw --> ro: Confirm the modifying branch is not busy
-  Aufs rejects the request if any of these conditions are true.
-  - a file on the branch is mmap-ed.
-  - a regular file on the branch is opened for write and there is no
-    same named entry on the upper branch.