Add VIRTIO_F_NOTIFICATION_DATA support for vDPA transport.
If this feature is negotiated, the driver passes extra data when kicking
a virtqueue.
A device that offers this feature needs to implement the
kick_vq_with_data callback.
kick_vq_with_data receives the vDPA device and data.
data includes:
16 bits vqn and 16 bits next available index for split virtqueues.
16 bits vqs, 15 least significant bits of next available index
and 1 bit next_wrap for packed virtqueues.
This patch follows a patch [1] by Viktor Prutyanov which adds support
for the MMIO, channel I/O and modern PCI transports.
Signed-off-by: Alvaro Karsz <alvaro.karsz@xxxxxxxxxxxxx>
---
drivers/virtio/virtio_vdpa.c | 23 +++++++++++++++++++++--
include/linux/vdpa.h | 9 +++++++++
2 files changed, 30 insertions(+), 2 deletions(-)
diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
index d7f5af62dda..737c1f36d32 100644
--- a/drivers/virtio/virtio_vdpa.c
+++ b/drivers/virtio/virtio_vdpa.c
@@ -112,6 +112,17 @@ static bool virtio_vdpa_notify(struct virtqueue *vq)
return true;
}
+static bool virtio_vdpa_notify_with_data(struct virtqueue *vq)
+{
+ struct vdpa_device *vdpa = vd_get_vdpa(vq->vdev);
+ const struct vdpa_config_ops *ops = vdpa->config;
+ u32 data = vring_notification_data(vq);
+
+ ops->kick_vq_with_data(vdpa, data);
+
+ return true;
+}
+
static irqreturn_t virtio_vdpa_config_cb(void *private)
{
struct virtio_vdpa_device *vd_dev = private;
@@ -138,6 +149,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
struct device *dma_dev;
const struct vdpa_config_ops *ops = vdpa->config;
struct virtio_vdpa_vq_info *info;
+ bool (*notify)(struct virtqueue *vq) = virtio_vdpa_notify;
struct vdpa_callback cb;
struct virtqueue *vq;
u64 desc_addr, driver_addr, device_addr;
@@ -154,6 +166,14 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
if (index >= vdpa->nvqs)
return ERR_PTR(-ENOENT);
+ /* We cannot accept VIRTIO_F_NOTIFICATION_DATA without kick_vq_with_data */
+ if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA)) {
+ if (ops->kick_vq_with_data)
+ notify = virtio_vdpa_notify_with_data;
+ else
+ __virtio_clear_bit(vdev, VIRTIO_F_NOTIFICATION_DATA);
+ }
+
/* Queue shouldn't already be set up. */
if (ops->get_vq_ready(vdpa, index))
return ERR_PTR(-ENOENT);
@@ -183,8 +203,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
dma_dev = vdpa_get_dma_dev(vdpa);
vq = vring_create_virtqueue_dma(index, max_num, align, vdev,
true, may_reduce_num, ctx,
- virtio_vdpa_notify, callback,
- name, dma_dev);
+ notify, callback, name, dma_dev);
if (!vq) {
err = -ENOMEM;
goto error_new_virtqueue;
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index 43f59ef10cc..04cdaad77dd 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -143,6 +143,14 @@ struct vdpa_map_file {
* @kick_vq: Kick the virtqueue
* @vdev: vdpa device
* @idx: virtqueue index
+ * @kick_vq_with_data: Kick the virtqueue and supply extra data
+ * (only if VIRTIO_F_NOTIFICATION_DATA is negotiated)
+ * @vdev: vdpa device
+ * @data for split virtqueue:
+ * 16 bits vqn and 16 bits next available index.
+ * @data for packed virtqueue:
+ * 16 bits vqn, 15 least significant bits of
+ * next available index and 1 bit next_wrap.
* @set_vq_cb: Set the interrupt callback function for
* a virtqueue
* @vdev: vdpa device
@@ -300,6 +308,7 @@ struct vdpa_config_ops {
u64 device_area);
void (*set_vq_num)(struct vdpa_device *vdev, u16 idx, u32 num);
void (*kick_vq)(struct vdpa_device *vdev, u16 idx);
+ void (*kick_vq_with_data)(struct vdpa_device *vdev, u32 data);
void (*set_vq_cb)(struct vdpa_device *vdev, u16 idx,
struct vdpa_callback *cb);
void (*set_vq_ready)(struct vdpa_device *vdev, u16 idx, bool ready);
--
2.34.1
