[dpdk-dev] [PATCH 6/6] virtio: add virtio v1.0 support

[Tan, Jianfeng]

> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Yuanhan Liu
> Sent: Thursday, December 10, 2015 11:54 AM
> To: dev at dpdk.org
> Subject: [dpdk-dev] [PATCH 6/6] virtio: add virtio v1.0 support
> 
...
> Signed-off-by: Yuanhan Liu <yuanhan.liu at linux.intel.com>
> ---
>  drivers/net/virtio/virtio_ethdev.c |  16 +-
>  drivers/net/virtio/virtio_ethdev.h |   3 +-
>  drivers/net/virtio/virtio_pci.c    | 313
> ++++++++++++++++++++++++++++++++++++-
>  drivers/net/virtio/virtio_pci.h    |  65 ++++++++
>  drivers/net/virtio/virtqueue.h     |   2 +
>  5 files changed, 395 insertions(+), 4 deletions(-)
> 

As legacy VIRTIO_WRITE_REG_XXXs are only used in virtio_pci.c, move these definitions into virtio_pci.c?

> diff --git a/drivers/net/virtio/virtio_ethdev.c
> b/drivers/net/virtio/virtio_ethdev.c
> index 9847ed8..1f9de01 100644
> --- a/drivers/net/virtio/virtio_ethdev.c
> +++ b/drivers/net/virtio/virtio_ethdev.c
> @@ -927,7 +927,7 @@ virtio_vlan_filter_set(struct rte_eth_dev *dev,
> uint16_t vlan_id, int on)
>  	return virtio_send_command(hw->cvq, &ctrl, &len, 1);
>  }
> 
> -static void
> +static int
>  virtio_negotiate_features(struct virtio_hw *hw)
>  {
>  	uint64_t host_features;
> @@ -949,6 +949,17 @@ virtio_negotiate_features(struct virtio_hw *hw)
>  	hw->guest_features = vtpci_negotiate_features(hw, host_features);
>  	PMD_INIT_LOG(DEBUG, "features after negotiate = %"PRIx64,
>  		hw->guest_features);
> +
> +	if (hw->modern) {
> +		if (!vtpci_with_feature(hw, VIRTIO_F_VERSION_1)) {
> +			PMD_INIT_LOG(ERR,
> +				"VIRTIO_F_VERSION_1 features is not
> enabled");
> +			return -1;
> +		}
> +		vtpci_set_status(hw,
> VIRTIO_CONFIG_STATUS_FEATURES_OK);


As per Linux code drivers/virtio/virtio.c:virtio_finalize_features(), vtpci_set_status() may fail, and there's a double check.
Is it necessary here?


> +	}
> +
> +	return 0;
>  }
> 
>  /*
> @@ -1032,7 +1043,8 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
> 
>  	/* Tell the host we've known how to drive the device. */
>  	vtpci_set_status(hw, VIRTIO_CONFIG_STATUS_DRIVER);
> -	virtio_negotiate_features(hw);
> +	if (virtio_negotiate_features(hw) < 0)
> +		return -1;
> 
>  	/* If host does not support status then disable LSC */
>  	if (!vtpci_with_feature(hw, VIRTIO_NET_F_STATUS))
> diff --git a/drivers/net/virtio/virtio_ethdev.h
> b/drivers/net/virtio/virtio_ethdev.h
> index ae2d47d..fed9571 100644
> --- a/drivers/net/virtio/virtio_ethdev.h
> +++ b/drivers/net/virtio/virtio_ethdev.h
> @@ -64,7 +64,8 @@
>  	 1u << VIRTIO_NET_F_CTRL_VQ	  |	\
>  	 1u << VIRTIO_NET_F_CTRL_RX	  |	\
>  	 1u << VIRTIO_NET_F_CTRL_VLAN	  |	\
> -	 1u << VIRTIO_NET_F_MRG_RXBUF)
> +	 1u << VIRTIO_NET_F_MRG_RXBUF	  |	\
> +	 1ULL << VIRTIO_F_VERSION_1)
> 
>  /*
>   * CQ function prototype
> diff --git a/drivers/net/virtio/virtio_pci.c b/drivers/net/virtio/virtio_pci.c
> index 26b0a0c..7862d7f 100644
> --- a/drivers/net/virtio/virtio_pci.c
> +++ b/drivers/net/virtio/virtio_pci.c
> @@ -31,6 +31,7 @@
>   *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
> DAMAGE.
>   */
>  #include <stdint.h>
> +#include <linux/pci_regs.h>

Put this "include" into macro RTE_EXEC_ENV_LINUXAPP followed?

> 
>  #ifdef RTE_EXEC_ENV_LINUXAPP
>   #include <dirent.h>
> @@ -448,6 +449,205 @@ static const struct virtio_pci_ops legacy_ops = {
>  };
> 
> 
...
> +
> +static uint16_t
> +modern_set_irq(struct virtio_hw *hw __rte_unused, uint16_t vec
> __rte_unused)
> +{
> +	/* FIXME: xxx */
> +	return 0;
> +}

If not going to support LSC, please give clear indication at related doc. My concern is: this will affect
some users, who are using LSC in legacy virtio. (If LSC works well on legacy virtio?).

> +
> +static uint16_t
> +modern_get_queue_num(struct virtio_hw *hw, uint16_t queue_id)
> +{
> +	modern_write16(queue_id, &hw->common_cfg->queue_select);
> +	return modern_read16(&hw->common_cfg->queue_size);
> +}
> +
...
> 
> +static inline void *
> +get_cfg_addr(struct rte_pci_device *dev, struct virtio_pci_cap *cap)
> +{
> +	uint8_t  bar    = cap->bar;
> +	uint32_t length = cap->length;
> +	uint32_t offset = cap->offset;
> +	uint8_t *base;
> +

Use a macro to substitute hardcoded "5"?

> +	if (unlikely(bar > 5)) {
> +		PMD_INIT_LOG(ERR, "invalid bar: %u", bar);
> +		return NULL;
> +	}
> +
...
>  int
>  vtpci_init(struct rte_pci_device *dev, struct virtio_hw *hw)
>  {
> -	hw->vtpci_ops = &legacy_ops;
> +	hw->dev = dev;
> 
> +	/*
> +	 * Try if we can succeed reading virtio pci caps, which exists
> +	 * only on modern pci device. If failed, we fallback to legacy
> +	 * virtio hanlding.

hanlding -> handling

Thanks,
Jianfeng

> +	 */
...
> +
>  	struct vq_desc_extra {
>  		void              *cookie;
>  		uint16_t          ndescs;
> --
> 1.9.0