[PATCH 2/5] tools/kvm/virtio: Add new iov helper

Aneesh Kumar K.V
2011-06-18T17:49:22Z

This add the in and out iovec to seperate array

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
---
tools/kvm/include/kvm/virtio.h | 3 +++
tools/kvm/virtio/core.c | 32 ++++++++++++++++++++++++++++++++
2 files changed, 35 insertions(+), 0 deletions(-)

diff --git a/tools/kvm/include/kvm/virtio.h b/tools/kvm/include/kvm/virtio.h
index 66e6fdb..b962705 100644
--- a/tools/kvm/include/kvm/virtio.h
+++ b/tools/kvm/include/kvm/virtio.h
@@ -50,6 +50,9 @@ static inline void *guest_pfn_to_host(struct kvm *kvm, u32 pfn)
struct vring_used_elem *virt_queue__set_used_elem(struct virt_queue *queue, u32 head, u32 len);

u16 virt_queue__get_iov(struct virt_queue *queue, struct iovec iov[], u16 *out, u16 *in, struct kvm *kvm);
+u16 virt_queue__get_inout_iov(struct kvm *kvm, struct virt_queue *queue,
+ struct iovec in_iov[], struct iovec out_iov[],
+ u16 *in, u16 *out);

void virt_queue__trigger_irq(struct virt_queue *vq, int irq, u8 *isr, struct kvm *kvm);

diff --git a/tools/kvm/virtio/core.c b/tools/kvm/virtio/core.c
index 2b3503d..d28cfc6 100644
--- a/tools/kvm/virtio/core.c
+++ b/tools/kvm/virtio/core.c
@@ -58,6 +58,38 @@ u16 virt_queue__get_iov(struct virt_queue *queue, struct iovec iov[], u16 *out,
return head;
}

+/* in and out are relative to guest */
+u16 virt_queue__get_inout_iov(struct kvm *kvm, struct virt_queue *queue,
+ struct iovec in_iov[], struct iovec out_iov[],
+ u16 *in, u16 *out)
+{
+ u16 head, idx;
+ struct vring_desc *desc;
+
+ idx = head = virt_queue__pop(queue);
+ *out = *in = 0;
+ do {
+ desc = virt_queue__get_desc(queue, idx);
+ if (desc->flags & VRING_DESC_F_WRITE) {
+ in_iov[*in].iov_base = guest_flat_to_host(kvm,
+ desc->addr);
+ in_iov[*in].iov_len = desc->len;
+ (*in)++;
+ } else {
+ out_iov[*out].iov_base = guest_flat_to_host(kvm,
+ desc->addr);
+ out_iov[*out].iov_len = desc->len;
+ (*out)++;
+ }
+ if (desc->flags & VRING_DESC_F_NEXT)
+ idx = desc->next;
+ else
+ break;
+ } while (1);
+ return head;
+}
+
+
void virt_queue__trigger_irq(struct virt_queue *vq, int irq, u8 *isr, struct kvm *kvm)
{
if (vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
--
1.7.4.1