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authorEugenio Pérez <eperezma@redhat.com>2022-03-14 18:34:45 +0100
committerJason Wang <jasowang@redhat.com>2022-03-15 13:57:44 +0800
commitdafb34c9926a38b3bfc4ab8f35a99ca1c706648c (patch)
tree8e9470efd57e9f72ecdabcd6d4440acffafb865b
parent4725a4181b0fd5b646c51f079d7eac753b14b094 (diff)
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virtio: Add vhost_svq_get_vring_addr
It reports the shadow virtqueue address from qemu virtual address space. Since this will be different from the guest's vaddr, but the device can access it, SVQ takes special care about its alignment & lack of garbage data. It assumes that IOMMU will work in host_page_size ranges for that. Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com>
-rw-r--r--hw/virtio/vhost-shadow-virtqueue.c29
-rw-r--r--hw/virtio/vhost-shadow-virtqueue.h9
2 files changed, 38 insertions, 0 deletions
diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c
index 5193284..573ac0d 100644
--- a/hw/virtio/vhost-shadow-virtqueue.c
+++ b/hw/virtio/vhost-shadow-virtqueue.c
@@ -107,6 +107,35 @@ void vhost_svq_set_svq_call_fd(VhostShadowVirtqueue *svq, int call_fd)
}
/**
+ * Get the shadow vq vring address.
+ * @svq: Shadow virtqueue
+ * @addr: Destination to store address
+ */
+void vhost_svq_get_vring_addr(const VhostShadowVirtqueue *svq,
+ struct vhost_vring_addr *addr)
+{
+ addr->desc_user_addr = (uint64_t)(intptr_t)svq->vring.desc;
+ addr->avail_user_addr = (uint64_t)(intptr_t)svq->vring.avail;
+ addr->used_user_addr = (uint64_t)(intptr_t)svq->vring.used;
+}
+
+size_t vhost_svq_driver_area_size(const VhostShadowVirtqueue *svq)
+{
+ size_t desc_size = sizeof(vring_desc_t) * svq->vring.num;
+ size_t avail_size = offsetof(vring_avail_t, ring) +
+ sizeof(uint16_t) * svq->vring.num;
+
+ return ROUND_UP(desc_size + avail_size, qemu_real_host_page_size);
+}
+
+size_t vhost_svq_device_area_size(const VhostShadowVirtqueue *svq)
+{
+ size_t used_size = offsetof(vring_used_t, ring) +
+ sizeof(vring_used_elem_t) * svq->vring.num;
+ return ROUND_UP(used_size, qemu_real_host_page_size);
+}
+
+/**
* Set a new file descriptor for the guest to kick the SVQ and notify for avail
*
* @svq: The svq
diff --git a/hw/virtio/vhost-shadow-virtqueue.h b/hw/virtio/vhost-shadow-virtqueue.h
index 9e12f77..82cea1c 100644
--- a/hw/virtio/vhost-shadow-virtqueue.h
+++ b/hw/virtio/vhost-shadow-virtqueue.h
@@ -11,9 +11,14 @@
#define VHOST_SHADOW_VIRTQUEUE_H
#include "qemu/event_notifier.h"
+#include "hw/virtio/virtio.h"
+#include "standard-headers/linux/vhost_types.h"
/* Shadow virtqueue to relay notifications */
typedef struct VhostShadowVirtqueue {
+ /* Shadow vring */
+ struct vring vring;
+
/* Shadow kick notifier, sent to vhost */
EventNotifier hdev_kick;
/* Shadow call notifier, sent to vhost */
@@ -37,6 +42,10 @@ bool vhost_svq_valid_features(uint64_t features, Error **errp);
void vhost_svq_set_svq_kick_fd(VhostShadowVirtqueue *svq, int svq_kick_fd);
void vhost_svq_set_svq_call_fd(VhostShadowVirtqueue *svq, int call_fd);
+void vhost_svq_get_vring_addr(const VhostShadowVirtqueue *svq,
+ struct vhost_vring_addr *addr);
+size_t vhost_svq_driver_area_size(const VhostShadowVirtqueue *svq);
+size_t vhost_svq_device_area_size(const VhostShadowVirtqueue *svq);
void vhost_svq_stop(VhostShadowVirtqueue *svq);