On 25.02.2019 10:51, Changpeng Liu wrote:
> This patch adds new vhost user messages GET_CONFIG and SET_CONFIG
> used to get/set virtio device's PCI configuration space.
Beside the fact that some additional description and reasoning required,
I do not see the usage of this feature. You're defining the flag
VHOST_USER_PROTOCOL_F_CONFIG, but it's never used. So, none of dpdk vhost
backends (vdpa, vhost-user) will use this feature.
You, probably, missed adding it to VHOST_USER_PROTOCOL_FEATURES or
VDPA_SUPPORTED_PROTOCOL_FEATURES.
>From the other side, current implementation forces application to properly
implement the get/set_config callbacks. Otherwise, receiving of the messages
will result in RTE_VHOST_MSG_RESULT_ERR and subsequent vhost disconnection.
This looks strange, because supported protocol features normally enabled by
default. Am I misunderstood something ?
One more thing. According to spec: "vhost-user slave uses zero length of
payload to indicate an error to vhost-user master". However, current version
of 'vhost_user_get_config' replies with size equal to 'sizeof(uint64_t)'.
Best regards, Ilya Maximets.
> Signed-off-by: Changpeng Liu <changpeng....@intel.com>
> Reviewed-by: Darek Stojaczyk <dariusz.stojac...@intel.com>
> ---
> lib/librte_vhost/rte_vhost.h | 8 ++++++++
> lib/librte_vhost/vhost_user.c | 44
> +++++++++++++++++++++++++++++++++++++++++++
> lib/librte_vhost/vhost_user.h | 16 ++++++++++++++++
> 3 files changed, 68 insertions(+)
>
> diff --git a/lib/librte_vhost/rte_vhost.h b/lib/librte_vhost/rte_vhost.h
> index 2753670..ab710ce 100644
> --- a/lib/librte_vhost/rte_vhost.h
> +++ b/lib/librte_vhost/rte_vhost.h
> @@ -63,6 +63,10 @@
> #define VHOST_USER_PROTOCOL_F_PAGEFAULT 8
> #endif
>
> +#ifndef VHOST_USER_PROTOCOL_F_CONFIG
> +#define VHOST_USER_PROTOCOL_F_CONFIG 9
> +#endif
> +
> #ifndef VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD
> #define VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD 10
> #endif
> @@ -173,6 +177,10 @@ struct vhost_device_ops {
>
> int (*vring_state_changed)(int vid, uint16_t queue_id, int enable);
> /**< triggered when a vring is enabled or disabled */
>
> + int (*get_config)(int vid, uint8_t *config, uint32_t config_len);
> + int (*set_config)(int vid, uint8_t *config, uint32_t offset,
> + uint32_t len, uint32_t flags);
> +
> /**
> * Features could be changed after the feature negotiation.
> * For example, VHOST_F_LOG_ALL will be set/cleared at the
> diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
> index b086ad9..8e42734 100644
> --- a/lib/librte_vhost/vhost_user.c
> +++ b/lib/librte_vhost/vhost_user.c
> @@ -73,6 +73,8 @@
> [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",
> @@ -359,6 +361,46 @@
> return RTE_VHOST_MSG_RESULT_OK;
> }
>
> +static int
> +vhost_user_get_config(struct virtio_net **pdev, struct VhostUserMsg *msg,
> + int main_fd __rte_unused)
> +{
> + struct virtio_net *dev = *pdev;
> +
> + if (!dev->notify_ops->get_config) {
> + msg->size = sizeof(uint64_t);
> + return RTE_VHOST_MSG_RESULT_REPLY;
> + }
> +
> + if (dev->notify_ops->get_config(dev->vid,
> + msg->payload.config.region,
> + msg->payload.config.size) != 0) {
> + msg->size = sizeof(uint64_t);
> + }
> +
> + return RTE_VHOST_MSG_RESULT_REPLY;
> +}
> +
> +static int
> +vhost_user_set_config(struct virtio_net **pdev, struct VhostUserMsg *msg,
> + int main_fd __rte_unused)
> +{
> + struct virtio_net *dev = *pdev;
> +
> + if (!dev->notify_ops->set_config)
> + return RTE_VHOST_MSG_RESULT_ERR;
> +
> + if (dev->notify_ops->set_config(dev->vid,
> + msg->payload.config.region,
> + msg->payload.config.offset,
> + msg->payload.config.size,
> + msg->payload.config.flags) != 0) {
> + return RTE_VHOST_MSG_RESULT_ERR;
> + }
> +
> + return RTE_VHOST_MSG_RESULT_OK;
> +}
> +
> /*
> * Reallocate virtio_dev and vhost_virtqueue data structure to make them on
> the
> * same numa node as the memory of vring descriptor.
> @@ -1725,6 +1767,8 @@ 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/librte_vhost/vhost_user.h b/lib/librte_vhost/vhost_user.h
> index 2a650fe..057cdec 100644
> --- a/lib/librte_vhost/vhost_user.h
> +++ b/lib/librte_vhost/vhost_user.h
> @@ -12,6 +12,11 @@
>
> /* refer to hw/virtio/vhost-user.c */
>
> +/*
> + * Maximum size of virtio device config space
> + */
> +#define VHOST_USER_MAX_CONFIG_SIZE 256
> +
> #define VHOST_MEMORY_MAX_NREGIONS 8
>
> #define VHOST_USER_PROTOCOL_FEATURES ((1ULL << VHOST_USER_PROTOCOL_F_MQ) | \
> @@ -49,6 +54,8 @@
> 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,
> @@ -60,6 +67,7 @@
> typedef enum VhostUserSlaveRequest {
> VHOST_USER_SLAVE_NONE = 0,
> VHOST_USER_SLAVE_IOTLB_MSG = 1,
> + VHOST_USER_SLAVE_CONFIG_CHANGE_MSG = 2,
> VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG = 3,
> VHOST_USER_SLAVE_MAX
> } VhostUserSlaveRequest;
> @@ -112,6 +120,13 @@
> uint64_t offset;
> } VhostUserVringArea;
>
> +typedef struct VhostUserConfig {
> + uint32_t offset;
> + uint32_t size;
> + uint32_t flags;
> + uint8_t region[VHOST_USER_MAX_CONFIG_SIZE];
> +} VhostUserConfig;
> +
> typedef struct VhostUserMsg {
> union {
> uint32_t master; /* a VhostUserRequest value */
> @@ -131,6 +146,7 @@
> struct vhost_vring_addr addr;
> VhostUserMemory memory;
> VhostUserLog log;
> + VhostUserConfig config;
> struct vhost_iotlb_msg iotlb;
> VhostUserCryptoSessionParam crypto_session;
> VhostUserVringArea area;
>
