Pull fscrypt updates from Ted Ts'o:
 "Various cleanups for the file system encryption feature"

* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/fscrypt:
  fscrypt: constify struct fscrypt_operations
  fscrypt: properly declare on-stack completion
  fscrypt: split supp and notsupp declarations into their own headers
  fscrypt: remove redundant assignment of res
  fscrypt: make fscrypt_operations.key_prefix a string
  fscrypt: remove unused 'mode' member of fscrypt_ctx
  ext4: don't allow encrypted operations without keys
  fscrypt: make test_dummy_encryption require a keyring key
  fscrypt: factor out bio specific functions
  fscrypt: pass up error codes from ->get_context()
  fscrypt: remove user-triggerable warning messages
  fscrypt: use EEXIST when file already uses different policy
  fscrypt: use ENOTDIR when setting encryption policy on nondirectory
  fscrypt: use ENOKEY when file cannot be created w/o key