OpenCloudOS-Kernel/drivers/virtio
Rusty Russell 42b36cc0ce virtio: Force use of power-of-two for descriptor ring sizes
The virtio descriptor rings of size N-1 were nicely set up to be
aligned to an N-byte boundary.  But as Anthony Liguori points out, the
free-running indices used by virtio require that the sizes be a power
of 2, otherwise we get problems on wrap (demonstrated with lguest).

So we replace the clever "2^n-1" scheme with a simple "align to page
boundary" scheme: this means that all virtio rings take at least two
pages, but it's safer than guessing cache alignment.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2007-11-12 13:59:40 +11:00
..
Kconfig Virtio helper routines for a descriptor ringbuffer implementation 2007-10-23 15:49:55 +10:00
Makefile Virtio helper routines for a descriptor ringbuffer implementation 2007-10-23 15:49:55 +10:00
config.c Virtio interface 2007-10-23 15:49:54 +10:00
virtio.c Module autoprobing support for virtio drivers. 2007-10-23 15:49:55 +10:00
virtio_ring.c virtio: Force use of power-of-two for descriptor ring sizes 2007-11-12 13:59:40 +11:00