Move map lookup into a separate function.

[jeff]

Summary

I'm not totally in love with the vm return codes. However, I am following a pattern that exists elsewhere in this file where RESOURCE_SHORTAGE means restart.

This should be functionally identical.

[kib]

sys/vm/vm_fault.c

878

You can write this cleaner IMO:

if (result == KERN_RESOURCE_SHORTAGE)
        goto RetryFault;
if (result != KERN_SUCCESS)
         return (result);

[markj]

sys/vm/vm_fault.c

878

Wouldn't that result in two comparisons instead of one in the common case?