Surface Currents: Finding Magnetic Field w/ Biot-Savart?

[MarkovMarakov]

Homework Statement

If a uniform current with current density s flows around a tube of radius a-- so it is a surface current, how might I find the magnetic field at some arbitrary position vector r?*

Homework Equations

Biot-Savart?

The Attempt at a Solution

I am guessing Biot-Savart? Or is there a simpler way since it has nice symmetry?

 

[Mindscrape]

Your geometry hasn't been described all that well, but why not ampere?

$$\int \mathbf{B} \cdot d\mathbf{l}=\int \mathbf{J} \cdot d\mathbf{a}$$