On Mon, Dec 07, 2015 at 12:07:28AM +0100, Thomas Monjalon wrote:
> 2015-12-02 15:53, Panu Matilainen:
> > This (and other changes in patch 2 breaks the librte_vhost ABI again, so
> > you'd need to at least add a deprecation note to 2.2 to be able to do it
> > in 2.3 at all according to the ABI policy.
> >
> > Perhaps a better option would be adding some padding to the structs now
> > for 2.2 since the vhost ABI is broken there anyway. That would at least
> > give a chance to keep it compatible from 2.2 to 2.3.
>
> Please could you point where the vhost ABI is broken in 2.2?
Thomas, here are the changes to rte_virtio_net.h:
$ git diff
381316f6a225139d22d39b5ab8d50c40607924ca..19d4d7ef2a216b5418d8edb5b004d1a58bba3cc1
\
-- lib/librte_vhost/rte_virtio_net.h >
diff --git a/lib/librte_vhost/rte_virtio_net.h
b/lib/librte_vhost/rte_virtio_net.h
index e3a21e5..426a70d 100644
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -89,6 +89,7 @@ struct vhost_virtqueue {
volatile uint16_t last_used_idx_res; /**< Used for multiple
devices reserving buffers. */
int callfd; /**< Used to notify the
guest (trigger interrupt). */
int kickfd; /**< Currently unused
as polling mode is enabled. */
+ int enabled;
struct buf_vector buf_vec[BUF_VECTOR_MAX]; /**< for
scatter RX. */
} __rte_cache_aligned;
@@ -96,7 +97,6 @@ struct vhost_virtqueue {
* Device structure contains all configuration information relating to the
device.
*/
struct virtio_net {
- struct vhost_virtqueue *virtqueue[VIRTIO_QNUM]; /**< Contains
all virtqueue information. */
struct virtio_memory *mem; /**< QEMU memory and memory
region information. */
uint64_t features; /**< Negotiated feature set. */
uint64_t protocol_features; /**< Negotiated
protocol feature set. */
@@ -104,7 +104,9 @@ struct virtio_net {
uint32_t flags; /**< Device flags. Only used to
check if device is running on data core. */
#define IF_NAME_SZ (PATH_MAX > IFNAMSIZ ? PATH_MAX : IFNAMSIZ)
char ifname[IF_NAME_SZ]; /**< Name of the tap
device or socket path. */
+ uint32_t virt_qp_nb; /**< number of queue pair we
have allocated */
void *priv; /**< private context */
+ struct vhost_virtqueue *virtqueue[VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX];
/**< Contains all virtqueue information. */
} __rte_cache_aligned;
/**
@@ -131,7 +133,7 @@ struct virtio_memory {
};
/**
- * Device operations to add/remove device.
+ * Device and vring operations.
*
* Make sure to set VIRTIO_DEV_RUNNING to the device flags in new_device and
* remove it in destroy_device.
@@ -140,12 +142,18 @@ struct virtio_memory {
struct virtio_net_device_ops {
int (*new_device)(struct virtio_net *); /**< Add device. */
void (*destroy_device)(volatile struct virtio_net *); /**< Remove
device. */
+
+ int (*vring_state_changed)(struct virtio_net *dev, uint16_t queue_id,
int enable); /**< triggered when a vring is enabled or disabled */
};
static inline uint16_t __attribute__((always_inline))
rte_vring_available_entries(struct virtio_net *dev, uint16_t queue_id)
{
struct vhost_virtqueue *vq = dev->virtqueue[queue_id];
+
+ if (!vq->enabled)
+ return 0;
+
return *(volatile uint16_t *)&vq->avail->idx - vq->last_used_idx_res;
}
--yliu
