From fc6f666f00182fe587068bd45e4e9e6d135d03fb Mon Sep 17 00:00:00 2001 From: Ladi Prosek Date: Wed, 5 Oct 2016 17:22:23 +0200 Subject: [PATCH 1/8] virtio: introduce virtqueue_unmap_sg() RH-Author: Ladi Prosek Message-id: <1475666548-9186-2-git-send-email-lprosek@redhat.com> Patchwork-id: 72480 O-Subject: [RHEL-7.4 qemu-kvm v2 PATCH 1/6] virtio: introduce virtqueue_unmap_sg() Bugzilla: 1393484 RH-Acked-by: Paolo Bonzini RH-Acked-by: Michael S. Tsirkin RH-Acked-by: Stefan Hajnoczi From: Jason Wang Factor out sg unmapping logic. This will be reused by the patch that can discard descriptor. Cc: Michael S. Tsirkin Cc: Andrew James Signed-off-by: Jason Wang Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin (cherry picked from commit ce317461573bac12b10d67699b4ddf1f97cf066c) Signed-off-by: Ladi Prosek Signed-off-by: Miroslav Rezanina --- hw/virtio/virtio.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 0df4ed3..5ee899a 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -228,14 +228,12 @@ int virtio_queue_empty(VirtQueue *vq) return vring_avail_idx(vq) == vq->last_avail_idx; } -void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, - unsigned int len, unsigned int idx) +static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem, + unsigned int len) { unsigned int offset; int i; - trace_virtqueue_fill(vq, elem, len, idx); - offset = 0; for (i = 0; i < elem->in_num; i++) { size_t size = MIN(len - offset, elem->in_sg[i].iov_len); @@ -251,6 +249,14 @@ void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, cpu_physical_memory_unmap(elem->out_sg[i].iov_base, elem->out_sg[i].iov_len, 0, elem->out_sg[i].iov_len); +} + +void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem, + unsigned int len, unsigned int idx) +{ + trace_virtqueue_fill(vq, elem, len, idx); + + virtqueue_unmap_sg(vq, elem, len); idx = (idx + vring_used_idx(vq)) % vq->vring.num; -- 1.8.3.1