How to get minor number in block driver transfer request
 

I am porting a block driver from 2.4 to 2.6 linux. I need to know the minor number in the transfer request. The transfer request is only passed the request_queue_t structure and I do not see how to get the device number, specifically the minor number form anything in that structure.
How do I determine the minor number in a block driver transfer function?
( In 2.4 it was done with a CURRENT_DEV macro which access a field that is no longer in the request_queue_t structure.

This is my first post, so let me know if I'm missing some posting edicate here.
Thanks.