RE: [PATCH v6 03/16] vhost: add vhost msg support

["Xia, Chenbo" <chenbo.xia@intel.com>]

Hi Andy,

> -----Original Message-----
> From: Pei, Andy <andy.pei@intel.com>
> Sent: Thursday, April 21, 2022 4:34 PM
> To: dev@dpdk.org
> Cc: Xia, Chenbo <chenbo.xia@intel.com>; maxime.coquelin@redhat.com; Cao,
> Gang <gang.cao@intel.com>; Liu, Changpeng <changpeng.liu@intel.com>
> Subject: [PATCH v6 03/16] vhost: add vhost msg support
> 
> Add support for VHOST_USER_GET_CONFIG and VHOST_USER_SET_CONFIG.
> VHOST_USER_GET_CONFIG and VHOST_USER_SET_CONFIG message is only
> supported by virtio blk VDPA device.
> 
> Signed-off-by: Andy Pei <andy.pei@intel.com>
> ---
>  lib/vhost/vhost_user.c | 69
> ++++++++++++++++++++++++++++++++++++++++++++++++++
>  lib/vhost/vhost_user.h | 13 ++++++++++
>  2 files changed, 82 insertions(+)
> 
> diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c
> index 1d39067..3780804 100644
> --- a/lib/vhost/vhost_user.c
> +++ b/lib/vhost/vhost_user.c
> @@ -80,6 +80,8 @@
>  	[VHOST_USER_NET_SET_MTU]  = "VHOST_USER_NET_SET_MTU",
>  	[VHOST_USER_SET_SLAVE_REQ_FD]  = "VHOST_USER_SET_SLAVE_REQ_FD",
>  	[VHOST_USER_IOTLB_MSG]  = "VHOST_USER_IOTLB_MSG",
> +	[VHOST_USER_GET_CONFIG]  = "VHOST_USER_GET_CONFIG",
> +	[VHOST_USER_SET_CONFIG]  = "VHOST_USER_SET_CONFIG",
>  	[VHOST_USER_CRYPTO_CREATE_SESS] = "VHOST_USER_CRYPTO_CREATE_SESS",
>  	[VHOST_USER_CRYPTO_CLOSE_SESS] = "VHOST_USER_CRYPTO_CLOSE_SESS",
>  	[VHOST_USER_POSTCOPY_ADVISE]  = "VHOST_USER_POSTCOPY_ADVISE",
> @@ -2542,6 +2544,71 @@ static int is_vring_iotlb(struct virtio_net *dev,
>  }
> 
>  static int
> +vhost_user_get_config(struct virtio_net **pdev,
> +			struct vhu_msg_context *ctx,
> +			int main_fd __rte_unused)
> +{
> +	struct virtio_net *dev = *pdev;
> +	struct rte_vdpa_device *vdpa_dev = dev->vdpa_dev;
> +	int ret = 0;
> +
> +	if (vdpa_dev->ops->get_config) {
> +		ret = vdpa_dev->ops->get_config(dev->vid,
> +					   ctx->msg.payload.cfg.region,
> +					   ctx->msg.payload.cfg.size);
> +		if (ret != 0) {
> +			ctx->msg.size = 0;
> +			VHOST_LOG_CONFIG(ERR,
> +					 "(%s) get_config() return error!\n",
> +					 dev->ifname);
> +		}
> +	} else {
> +		VHOST_LOG_CONFIG(ERR, "(%s) get_config() not supportted!\n",

Supported 

> +				 dev->ifname);
> +	}
> +
> +	return RTE_VHOST_MSG_RESULT_REPLY;
> +}
> +
> +static int
> +vhost_user_set_config(struct virtio_net **pdev,
> +			struct vhu_msg_context *ctx,
> +			int main_fd __rte_unused)
> +{
> +	struct virtio_net *dev = *pdev;
> +	struct rte_vdpa_device *vdpa_dev = dev->vdpa_dev;
> +	int ret = 0;
> +
> +	if (ctx->msg.size != sizeof(struct vhost_user_config)) {

I think you should do sanity check on payload.cfg.size and make sure it's smaller
than VHOST_USER_MAX_CONFIG_SIZE

and same check for offset

> +		VHOST_LOG_CONFIG(ERR,
> +			"(%s) invalid set config msg size: %"PRId32" != %d\n",
> +			dev->ifname, ctx->msg.size,

Based on you will change the log too, payload.cfg.size is uint32_t,
so PRId32 -> PRIu32

> +			(int)sizeof(struct vhost_user_config));

So this can be %u

> +		goto OUT;
> +	}
> +
> +	if (vdpa_dev->ops->set_config) {
> +		ret = vdpa_dev->ops->set_config(dev->vid,
> +			ctx->msg.payload.cfg.region,
> +			ctx->msg.payload.cfg.offset,
> +			ctx->msg.payload.cfg.size,
> +			ctx->msg.payload.cfg.flags);
> +		if (ret)
> +			VHOST_LOG_CONFIG(ERR,
> +					 "(%s) set_config() return error!\n",
> +					 dev->ifname);
> +	} else {
> +		VHOST_LOG_CONFIG(ERR, "(%s) set_config() not supportted!\n",

Supported

> +				 dev->ifname);
> +	}
> +
> +	return RTE_VHOST_MSG_RESULT_OK;
> +
> +OUT:

Lower case looks better

> +	return RTE_VHOST_MSG_RESULT_ERR;
> +}

Almost all handlers need check on expected fd num (this case is 0), so the above new
handlers should also do that. Please refer to validate_msg_fds in other handlers.

BTW, you can wait for review for other patches and send new versions later.

Thanks,
Chenbo

> +
> +static int
>  vhost_user_iotlb_msg(struct virtio_net **pdev,
>  			struct vhu_msg_context *ctx,
>  			int main_fd __rte_unused)
> @@ -2782,6 +2849,8 @@ typedef int (*vhost_message_handler_t)(struct
> virtio_net **pdev,
>  	[VHOST_USER_NET_SET_MTU] = vhost_user_net_set_mtu,
>  	[VHOST_USER_SET_SLAVE_REQ_FD] = vhost_user_set_req_fd,
>  	[VHOST_USER_IOTLB_MSG] = vhost_user_iotlb_msg,
> +	[VHOST_USER_GET_CONFIG] = vhost_user_get_config,
> +	[VHOST_USER_SET_CONFIG] = vhost_user_set_config,
>  	[VHOST_USER_POSTCOPY_ADVISE] = vhost_user_set_postcopy_advise,
>  	[VHOST_USER_POSTCOPY_LISTEN] = vhost_user_set_postcopy_listen,
>  	[VHOST_USER_POSTCOPY_END] = vhost_user_postcopy_end,
> diff --git a/lib/vhost/vhost_user.h b/lib/vhost/vhost_user.h
> index c946cc2..97cfb2f 100644
> --- a/lib/vhost/vhost_user.h
> +++ b/lib/vhost/vhost_user.h
> @@ -50,6 +50,8 @@
>  	VHOST_USER_NET_SET_MTU = 20,
>  	VHOST_USER_SET_SLAVE_REQ_FD = 21,
>  	VHOST_USER_IOTLB_MSG = 22,
> +	VHOST_USER_GET_CONFIG = 24,
> +	VHOST_USER_SET_CONFIG = 25,
>  	VHOST_USER_CRYPTO_CREATE_SESS = 26,
>  	VHOST_USER_CRYPTO_CLOSE_SESS = 27,
>  	VHOST_USER_POSTCOPY_ADVISE = 28,
> @@ -125,6 +127,16 @@
>  	uint16_t queue_size;
>  } VhostUserInflight;
> 
> +#define VHOST_USER_MAX_CONFIG_SIZE		256
> +
> +/** Get/set config msg payload */
> +struct vhost_user_config {
> +	uint32_t offset;
> +	uint32_t size;
> +	uint32_t flags;
> +	uint8_t region[VHOST_USER_MAX_CONFIG_SIZE];
> +};
> +
>  typedef struct VhostUserMsg {
>  	union {
>  		uint32_t master; /* a VhostUserRequest value */
> @@ -148,6 +160,7 @@
>  		VhostUserCryptoSessionParam crypto_session;
>  		VhostUserVringArea area;
>  		VhostUserInflight inflight;
> +		struct vhost_user_config cfg;
>  	} payload;
>  	/* Nothing should be added after the payload */
>  } __rte_packed VhostUserMsg;
> --
> 1.8.3.1