Merge remote-tracking branch 'ext4/dev'

diff --cc fs/buffer.c
Simple merge

diff --cc fs/ext4/inode.c
Simple merge

diff --cc fs/ext4/mballoc.c
Simple merge

diff --cc fs/ext4/super.c
Simple merge

diff --cc fs/fs-writeback.c
Simple merge

diff --cc fs/jbd2/journal.c
Simple merge