vhost: virtio 1.0 bugfix

There's a single change here, fixing a vhost bug where vhost initialization
 fails due to used ring alignment check being too strict.
 
 Cc: Rusty Russell <rusty@rustcorp.com.au>
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull vhost cleanup and virtio bugfix
 "There's a single change here, fixing a vhost bug where vhost
  initialization fails due to used ring alignment check being too
  strict"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost: relax used address alignment
  virtio_ring: document alignment requirements
This commit is contained in:
Linus Torvalds 2015-01-02 12:07:50 -08:00
commit d7e19bd882
2 changed files with 14 additions and 3 deletions

View file

@ -101,6 +101,13 @@ struct vring {
struct vring_used *used;
};
/* Alignment requirements for vring elements.
* When using pre-virtio 1.0 layout, these fall out naturally.
*/
#define VRING_AVAIL_ALIGN_SIZE 2
#define VRING_USED_ALIGN_SIZE 4
#define VRING_DESC_ALIGN_SIZE 16
/* The standard layout for the ring is a continuous chunk of memory which looks
* like this. We assume num is a power of 2.
*