Cherry-picked from origin/upstream-f2fs-stable-linux-4.4.y:
ba1ade7101 fscrypt: resolve some cherry-pick bugs
9e32f17d24 fscrypt: move to generic async completion
4ecacbed6e crypto: introduce crypto wait for async op
42d89da82b fscrypt: lock mutex before checking for bounce page pool
2286508d17 fscrypt: new helper function - fscrypt_prepare_setattr()
5cbdd42ad2 fscrypt: new helper function - fscrypt_prepare_lookup()
a31feba5c1 fscrypt: new helper function - fscrypt_prepare_rename()
95efafb623 fscrypt: new helper function - fscrypt_prepare_link()
2b4b4f98dd fscrypt: new helper function - fscrypt_file_open()
8c815f381c fscrypt: new helper function - fscrypt_require_key()
272e435025 fscrypt: remove unneeded empty fscrypt_operations structs
1034eeec51 fscrypt: remove ->is_encrypted()
32c0d3ae9d fscrypt: switch from ->is_encrypted() to IS_ENCRYPTED()
a4781dd1f1 fs, fscrypt: add an S_ENCRYPTED inode flag
ff0a3dbc93 fscrypt: clean up include file mess
bc4a61c60b fscrypt: fix dereference of NULL user_key_payload
a53dc7e005 fscrypt: make ->dummy_context() return bool
Change-Id: I461d742adc7b77177df91429a1fd9c8624a698d6
Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>
c2f631bf49