libqos: Added EVENT_IDX support

Added avail_event and NO_NOTIFY check before notifying.
Added used_event setting.

Signed-off-by: Marc Marí <marc.mari.barcelo@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

3 files changed, 32 insertions, 1 deletions

diff --git a/tests/libqos/virtio-pci.c b/tests/libqos/virtio-pci.c
index ab28717305..788ebaff46 100644
--- a/tests/libqos/virtio-pci.c
+++ b/tests/libqos/virtio-pci.c
@@ -203,6 +203,7 @@ static QVirtQueue *qvirtio_pci_virtqueue_setup(QVirtioDevice *d,
     vqpci->vq.num_free = vqpci->vq.size;
     vqpci->vq.align = QVIRTIO_PCI_ALIGN;
     vqpci->vq.indirect = (feat & QVIRTIO_F_RING_INDIRECT_DESC) != 0;
+    vqpci->vq.event = (feat & QVIRTIO_F_RING_EVENT_IDX) != 0;
 
     vqpci->msix_entry = -1;
     vqpci->msix_addr = 0;
diff --git a/tests/libqos/virtio.c b/tests/libqos/virtio.c
index 16eaf79425..128dbd0e9a 100644
--- a/tests/libqos/virtio.c
+++ b/tests/libqos/virtio.c
@@ -124,9 +124,13 @@ void qvring_init(const QGuestAllocator *alloc, QVirtQueue *vq, uint64_t addr)
     writew(vq->avail, 0);
     /* vq->avail->idx */
     writew(vq->avail + 2, 0);
+    /* vq->avail->used_event */
+    writew(vq->avail + 4 + (2 * vq->size), 0);
 
     /* vq->used->flags */
     writew(vq->used, 0);
+    /* vq->used->avail_event */
+    writew(vq->used+2+(sizeof(struct QVRingUsedElem)*vq->size), 0);
 }
 
 QVRingIndirectDesc *qvring_indirect_desc_setup(QVirtioDevice *d,
@@ -222,11 +226,32 @@ void qvirtqueue_kick(const QVirtioBus *bus, QVirtioDevice *d, QVirtQueue *vq,
 {
     /* vq->avail->idx */
     uint16_t idx = readl(vq->avail + 2);
+    /* vq->used->flags */
+    uint16_t flags;
+    /* vq->used->avail_event */
+    uint16_t avail_event;
 
     /* vq->avail->ring[idx % vq->size] */
     writel(vq->avail + 4 + (2 * (idx % vq->size)), free_head);
     /* vq->avail->idx */
     writel(vq->avail + 2, idx + 1);
 
-    bus->virtqueue_kick(d, vq);
+    /* Must read after idx is updated */
+    flags = readw(vq->avail);
+    avail_event = readw(vq->used + 4 +
+                                (sizeof(struct QVRingUsedElem) * vq->size));
+
+    /* < 1 because we add elements to avail queue one by one */
+    if ((flags & QVRING_USED_F_NO_NOTIFY) == 0 &&
+                            (!vq->event || (uint16_t)(idx-avail_event) < 1)) {
+        bus->virtqueue_kick(d, vq);
+    }
+}
+
+void qvirtqueue_set_used_event(QVirtQueue *vq, uint16_t idx)
+{
+    g_assert(vq->event);
+
+    /* vq->avail->used_event */
+    writew(vq->avail + 4 + (2 * vq->size), idx);
 }
diff --git a/tests/libqos/virtio.h b/tests/libqos/virtio.h
index cebccd21d1..70b3376360 100644
--- a/tests/libqos/virtio.h
+++ b/tests/libqos/virtio.h
@@ -26,6 +26,7 @@
 #define QVIRTIO_F_ANY_LAYOUT            0x08000000
 #define QVIRTIO_F_RING_INDIRECT_DESC    0x10000000
 #define QVIRTIO_F_RING_EVENT_IDX        0x20000000
+#define QVIRTIO_F_BAD_FEATURE           0x40000000
 
 #define QVRING_DESC_F_NEXT      0x1
 #define QVRING_DESC_F_WRITE     0x2
@@ -57,6 +58,7 @@ typedef struct QVRingAvail {
     uint16_t flags;
     uint16_t idx;
     uint16_t ring[0]; /* This is an array of uint16_t */
+    uint16_t used_event;
 } QVRingAvail;
 
 typedef struct QVRingUsedElem {
@@ -68,6 +70,7 @@ typedef struct QVRingUsed {
     uint16_t flags;
     uint16_t idx;
     QVRingUsedElem ring[0]; /* This is an array of QVRingUsedElem structs */
+    uint16_t avail_event;
 } QVRingUsed;
 
 typedef struct QVirtQueue {
@@ -80,6 +83,7 @@ typedef struct QVirtQueue {
     uint32_t num_free;
     uint32_t align;
     bool indirect;
+    bool event;
 } QVirtQueue;
 
 typedef struct QVRingIndirectDesc {
@@ -174,4 +178,5 @@ uint32_t qvirtqueue_add_indirect(QVirtQueue *vq, QVRingIndirectDesc *indirect);
 void qvirtqueue_kick(const QVirtioBus *bus, QVirtioDevice *d, QVirtQueue *vq,
                                                             uint32_t free_head);
 
+void qvirtqueue_set_used_event(QVirtQueue *vq, uint16_t idx);
 #endif