user virtual address to physical address

Hi,

I need to convert a user virtual address to its corresponding physical address.
I know that if the virtual address is from kernel, we could use virt_to_phys.
Is there a similar helper function
to convert user virtual address.?

Thanks,
Fredrick

Please elaborate the purpose,

User-space application allowed to have virtual address upto 3GB, assuming 1:3 address space split.
And its not mandatory for all user-space address to be valid and to have all user-space address to have a valid physical address mapping.

Thanks,
Chetan

Thanks,

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