Logical address to physical address translation

["Arun Babu" <arunbabu.n@xxxxxxxxx>]

Hi
I understand that to convert from logical to physical address space, we can use the macro __pa or virt_to_phys(), which applies for kernel memory space and not for user address space. (Am I correct?)
Further, if I want to get the physical frame number for a given logical address, can someone please suggest me the way? [Is writing a code to walk through the page tables the only way? or can we make use of an already existing function/module?] 

Thank you,
Arun