From: Nick Piggin <email@example.com>
Date: Wed, 14 Nov 2007 10:49:48 +1100
Sure, why not? Just cook up an iovec. pmd_numbers goes to offset
X and pmd_values goes to offset Y, with some helpers like what
we have in the networking already for recvmsg.
But why would you want readv() for this? The syscall thing
Paul asked me to translate into a read() doesn't provide
iovec-like behavior so I don't see why readv() is necessary