We're using the generic block buffer_head write_begin and write_end
functions. They call sop->dirty_inode() to update the inode i_size. We
didn't have that method wired up so updates to the inode in the write
path wasn't dirtying the inode item. Lost i_size updates would
trivially lose data but we first noticed this when looking at inode item
sequence numbers while overwriting.
Signed-off-by: Zach Brown <zab@versity.com>