On Sat, Oct 11, 2014 at 06:34:52AM -0700, Christoph Hellwig wrote:

I still very much disagree with the s_inode_fields indirection.  Please
find a patch below to remove it, and use a get_dquots super_block
operation instead.  This leads to less and better readable code,
and serves 4 bytes in every inode in the system.  Additionally the
indirection could easily be optimized away by directly passing the
dquot array in various functions, but for now I'd like to keep it
simple.

Indeed.  This "array of offsets" approach is asking for trouble.  Please,
don't go there - playing that way with type safety is a bad idea.