Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro...

Merge branch 'work.iov_iter' of git://git./linux/kernel/git/viro/vfs into iov-iter

* 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  switch new_sync_{read,write}() to ITER_UBUF
  new iov_iter flavour - ITER_UBUF
  keep iocb_flags() result cached in struct file
  iocb: delay evaluation of IS_SYNC(...) until we want to check IOCB_DSYNC
  struct file: use anonymous union member for rcuhead and llist
  btrfs_direct_write(): cleaner way to handle generic_write_sync() suppression