==== MFSH_VIRT2PHYS - Convert virtual to physical address ====

**Purpose**

Translate the address of a data buffer into a physical address.   

**Calling Sequence**

<code c>
int far pascal MFSH_VIRT2PHYS(ulVirtAddr, pulPhysAddr)

unsigned long ulVirtAddr;
unsigned long far * pulPhysAddr;
</code>

**Where**

//ulVirtAddr// contains the virtual address of the data area.   

//PhysAddr// is a pointer to a double word in which the helper returns the physical address of the data area. 

**Returns**

If no error is detected, a zero error code is returned. If an error is detected, the following error is returned:   

  * ERROR_PROTECTION_VIOLATION -- the supplied address is invalid. 

**Remarks**

This helper is for use by a mini-FSD with an imbedded device driver. It is the same as the standard device driver helper VIRTTOPHYS.