Somehow a naked u16 slipped into the glibc headers on my Ubuntu machine
(i386 2.17-0ubuntu5), breaking compile:
In file included from lguest.c:46:0:
/usr/include/linux/virtio_net.h:188:2: error: unknown type name ‘u16’
We use the kernel-style types anyway, just define them before the includes.
Also remove the advice on adding missing headers: that no longer works.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Lguest guests are UP, but the host is probably SMP, so real barriers are
required in case the device thread and the guest are on different CPUs.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
The virtio spec was missing a barrier in example code, so I went back
to look at the lguest code. Indeed, we need one.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
virtio requests are scatter-gather-style descriptors, but no
assumptions should be made about the layout. lguest was lazy here,
but saved by the fact that the network device hands all requests to
tun (which does it correctly) and console and random devices simply
use readv and writev.
Block devices, however, are broken: we convert to iovecs internally,
just make sure we handle the correctly.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We usually got away with ->next on the final entry being NULL, but it
finally bit me.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
This is a better location instead of having it in Documentation.
Signed-off-by: Davidlohr Bueso <dave@gnu.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (fixed compile)
Rusty Russell