virtio: make add_buf return capacity remaining

This API change means that virtio_net can tell how much capacity
remains for buffers.  It's necessarily fuzzy, since
VIRTIO_RING_F_INDIRECT_DESC means we can fit any number of descriptors
in one, *if* we can kmalloc.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Dinesh Subhraveti <dineshs@us.ibm.com>
This commit is contained in:
Rusty Russell
2009-09-23 22:26:31 -06:00
parent f68d24082e
commit 3c1b27d504
8 changed files with 19 additions and 15 deletions

View File

@@ -84,7 +84,7 @@ static void tell_host(struct virtio_balloon *vb, struct virtqueue *vq)
init_completion(&vb->acked);
/* We should always be able to add one buffer to an empty queue. */
if (vq->vq_ops->add_buf(vq, &sg, 1, 0, vb) != 0)
if (vq->vq_ops->add_buf(vq, &sg, 1, 0, vb) < 0)
BUG();
vq->vq_ops->kick(vq);