Re: [PATCH RFC 1/1] virtio-balloon: handle virtio-1 endianness
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: 2016-05-18 12:34:04
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On Wed, May 18, 2016 at 02:12:43PM +0200, Cornelia Huck wrote:
As virtio-1 devices use little endian on their queues, we need to make sure the pfns are in virtio32 format before we put them on the queue. Signed-off-by: Cornelia Huck <redacted>
I have a less hacky version that I was testing. Will post now.
quoted hunk ↗ jump to hunk
--- drivers/virtio/virtio_balloon.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c index 7b6d74f..89da06c 100644 --- a/drivers/virtio/virtio_balloon.c +++ b/drivers/virtio/virtio_balloon.c@@ -76,6 +76,7 @@ struct virtio_balloon { /* The array of pfns we tell the Host about. */ unsigned int num_pfns; u32 pfns[VIRTIO_BALLOON_ARRAY_PFNS_MAX]; + __virtio32 vpfns[VIRTIO_BALLOON_ARRAY_PFNS_MAX]; /* Memory statistics */ struct virtio_balloon_stat stats[VIRTIO_BALLOON_S_NR];@@ -115,8 +116,11 @@ static void tell_host(struct virtio_balloon *vb, struct virtqueue *vq) { struct scatterlist sg; unsigned int len; + int i; - sg_init_one(&sg, vb->pfns, sizeof(vb->pfns[0]) * vb->num_pfns); + for (i = 0; i < vb->num_pfns; i++) + vb->vpfns[i] = cpu_to_virtio32(vb->vdev, vb->pfns[i]); + sg_init_one(&sg, vb->vpfns, sizeof(vb->vpfns[0]) * vb->num_pfns); /* We should always be able to add one buffer to an empty queue. */ virtqueue_add_outbuf(vq, &sg, 1, vb, GFP_KERNEL);-- 2.6.6