Source that sets max_segments

[Spelic <spelic@shiftmail.org>]

Hello list
sorry this is a bit OT but I didn't know where to ask.
I am trying to raise max_segments above 128 by kernel recompile but it 
seems I am not able to.

I have identified this place in the sources

void blk_set_default_limits(struct queue_limits *lim)
{
         lim->max_segments = BLK_MAX_SEGMENTS;
....

so I have raised the value of corresponding enum BLK_MAX_SEGMENTS (which 
was indeed set at 128), but I was surprised to notice that after booting 
the new kernel the value is still stuck at 128, for all devices: sd*, 
md*, dm-* .

So such value must come from elsewhere, but where?

( I am on 3.4.x fwiw.... )

Thanks in advance