> -----Original Message-----
> From: Maxime Coquelin <maxime.coque...@redhat.com>
> Sent: Tuesday, January 26, 2021 1:14 AM
> To: dev@dpdk.org; Xia, Chenbo <chenbo....@intel.com>; olivier.m...@6wind.com;
> amore...@redhat.com; david.march...@redhat.com
> Cc: Maxime Coquelin <maxime.coque...@redhat.com>
> Subject: [PATCH v3 27/44] net/virtio: add Virtio-user features ops
>
> This patch introduces new callbacks for getting
> and setting Virtio features, and implements them
> for the different backend types.
>
> Signed-off-by: Maxime Coquelin <maxime.coque...@redhat.com>
> ---
> drivers/net/virtio/virtio_user/vhost.h | 2 +
> drivers/net/virtio/virtio_user/vhost_kernel.c | 150 +++++++++---------
> .../net/virtio/virtio_user/vhost_kernel_tap.c | 23 +++
> .../net/virtio/virtio_user/vhost_kernel_tap.h | 1 +
> drivers/net/virtio/virtio_user/vhost_user.c | 64 +++++++-
> drivers/net/virtio/virtio_user/vhost_vdpa.c | 38 +++--
> .../net/virtio/virtio_user/virtio_user_dev.c | 5 +-
> drivers/net/virtio/virtio_user_ethdev.c | 3 +-
> 8 files changed, 190 insertions(+), 96 deletions(-)
>
> diff --git a/drivers/net/virtio/virtio_user/vhost.h
> b/drivers/net/virtio/virtio_user/vhost.h
> index 5413ec6778..13a88c7671 100644
> --- a/drivers/net/virtio/virtio_user/vhost.h
> +++ b/drivers/net/virtio/virtio_user/vhost.h
> @@ -110,6 +110,8 @@ struct virtio_user_dev;
> struct virtio_user_backend_ops {
> int (*setup)(struct virtio_user_dev *dev);
> int (*set_owner)(struct virtio_user_dev *dev);
> + int (*get_features)(struct virtio_user_dev *dev, uint64_t *features);
> + int (*set_features)(struct virtio_user_dev *dev, uint64_t features);
> int (*send_request)(struct virtio_user_dev *dev,
> enum vhost_user_request req,
> void *arg);
> diff --git a/drivers/net/virtio/virtio_user/vhost_kernel.c
> b/drivers/net/virtio/virtio_user/vhost_kernel.c
> index b79dcad179..e46039e649 100644
> --- a/drivers/net/virtio/virtio_user/vhost_kernel.c
> +++ b/drivers/net/virtio/virtio_user/vhost_kernel.c
> @@ -38,6 +38,28 @@ struct vhost_memory_kernel {
> #define VHOST_SET_VRING_ERR _IOW(VHOST_VIRTIO, 0x22, struct vhost_vring_file)
> #define VHOST_NET_SET_BACKEND _IOW(VHOST_VIRTIO, 0x30, struct
> vhost_vring_file)
>
> +/* with below features, vhost kernel does not need to do the checksum and
> TSO,
> + * these info will be passed to virtio_user through virtio net header.
> + */
> +#define VHOST_KERNEL_GUEST_OFFLOADS_MASK \
> + ((1ULL << VIRTIO_NET_F_GUEST_CSUM) | \
> + (1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
> + (1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
> + (1ULL << VIRTIO_NET_F_GUEST_ECN) | \
> + (1ULL << VIRTIO_NET_F_GUEST_UFO))
> +
> +/* with below features, when flows from virtio_user to vhost kernel
> + * (1) if flows goes up through the kernel networking stack, it does not need
> + * to verify checksum, which can save CPU cycles;
> + * (2) if flows goes through a Linux bridge and outside from an interface
> + * (kernel driver), checksum and TSO will be done by GSO in kernel or even
> + * offloaded into real physical device.
> + */
> +#define VHOST_KERNEL_HOST_OFFLOADS_MASK \
> + ((1ULL << VIRTIO_NET_F_HOST_TSO4) | \
> + (1ULL << VIRTIO_NET_F_HOST_TSO6) | \
> + (1ULL << VIRTIO_NET_F_CSUM))
> +
> static uint64_t max_regions = 64;
>
> static void
> @@ -77,10 +99,57 @@ vhost_kernel_set_owner(struct virtio_user_dev *dev)
> return vhost_kernel_ioctl(dev->vhostfds[0], VHOST_SET_OWNER, NULL);
> }
>
> +static int
> +vhost_kernel_get_features(struct virtio_user_dev *dev, uint64_t *features)
> +{
> + int ret;
> + unsigned int tap_features;
> +
> + ret = vhost_kernel_ioctl(dev->vhostfds[0], VHOST_GET_FEATURES,
> features);
> + if (ret < 0) {
> + PMD_DRV_LOG(ERR, "Failed to get features");
> + return -1;
> + }
> +
> + ret = tap_support_features(&tap_features);
> + if (ret < 0) {
> + PMD_DRV_LOG(ERR, "Failed to get TAP features");
> + return -1;
> + }
> +
> + /* with tap as the backend, all these features are supported
> + * but not claimed by vhost-net, so we add them back when
> + * reporting to upper layer.
> + */
> + if (tap_features & IFF_VNET_HDR) {
> + *features |= VHOST_KERNEL_GUEST_OFFLOADS_MASK;
> + *features |= VHOST_KERNEL_HOST_OFFLOADS_MASK;
> + }
> +
> + /* vhost_kernel will not declare this feature, but it does
> + * support multi-queue.
> + */
> + if (tap_features & IFF_MULTI_QUEUE)
> + *features |= (1ull << VIRTIO_NET_F_MQ);
> +
> + return 0;
> +}
> +
> +static int
> +vhost_kernel_set_features(struct virtio_user_dev *dev, uint64_t features)
> +{
> + /* We don't need memory protection here */
> + features &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM);
> + /* VHOST kernel does not know about below flags */
> + features &= ~VHOST_KERNEL_GUEST_OFFLOADS_MASK;
> + features &= ~VHOST_KERNEL_HOST_OFFLOADS_MASK;
> + features &= ~(1ULL << VIRTIO_NET_F_MQ);
> +
> + return vhost_kernel_ioctl(dev->vhostfds[0], VHOST_SET_FEATURES,
> &features);
> +}
> +
> static uint64_t vhost_req_user_to_kernel[] = {
> [VHOST_USER_RESET_OWNER] = VHOST_RESET_OWNER,
> - [VHOST_USER_SET_FEATURES] = VHOST_SET_FEATURES,
> - [VHOST_USER_GET_FEATURES] = VHOST_GET_FEATURES,
> [VHOST_USER_SET_VRING_CALL] = VHOST_SET_VRING_CALL,
> [VHOST_USER_SET_VRING_NUM] = VHOST_SET_VRING_NUM,
> [VHOST_USER_SET_VRING_BASE] = VHOST_SET_VRING_BASE,
> @@ -150,51 +219,6 @@ prepare_vhost_memory_kernel(void)
> return vm;
> }
>
> -/* with below features, vhost kernel does not need to do the checksum and
> TSO,
> - * these info will be passed to virtio_user through virtio net header.
> - */
> -#define VHOST_KERNEL_GUEST_OFFLOADS_MASK \
> - ((1ULL << VIRTIO_NET_F_GUEST_CSUM) | \
> - (1ULL << VIRTIO_NET_F_GUEST_TSO4) | \
> - (1ULL << VIRTIO_NET_F_GUEST_TSO6) | \
> - (1ULL << VIRTIO_NET_F_GUEST_ECN) | \
> - (1ULL << VIRTIO_NET_F_GUEST_UFO))
> -
> -/* with below features, when flows from virtio_user to vhost kernel
> - * (1) if flows goes up through the kernel networking stack, it does not need
> - * to verify checksum, which can save CPU cycles;
> - * (2) if flows goes through a Linux bridge and outside from an interface
> - * (kernel driver), checksum and TSO will be done by GSO in kernel or even
> - * offloaded into real physical device.
> - */
> -#define VHOST_KERNEL_HOST_OFFLOADS_MASK \
> - ((1ULL << VIRTIO_NET_F_HOST_TSO4) | \
> - (1ULL << VIRTIO_NET_F_HOST_TSO6) | \
> - (1ULL << VIRTIO_NET_F_CSUM))
> -
> -static unsigned int
> -tap_support_features(void)
> -{
> - int tapfd;
> - unsigned int tap_features;
> -
> - tapfd = open(PATH_NET_TUN, O_RDWR);
> - if (tapfd < 0) {
> - PMD_DRV_LOG(ERR, "fail to open %s: %s",
> - PATH_NET_TUN, strerror(errno));
> - return -1;
> - }
> -
> - if (ioctl(tapfd, TUNGETFEATURES, &tap_features) == -1) {
> - PMD_DRV_LOG(ERR, "TUNGETFEATURES failed: %s", strerror(errno));
> - close(tapfd);
> - return -1;
> - }
> -
> - close(tapfd);
> - return tap_features;
> -}
> -
> static int
> vhost_kernel_send_request(struct virtio_user_dev *dev,
> enum vhost_user_request req,
> @@ -206,7 +230,6 @@ vhost_kernel_send_request(struct virtio_user_dev *dev,
> struct vhost_memory_kernel *vm = NULL;
> int vhostfd;
> unsigned int queue_sel;
> - unsigned int features;
>
> PMD_DRV_LOG(INFO, "%s", vhost_msg_strings[req]);
>
> @@ -219,17 +242,6 @@ vhost_kernel_send_request(struct virtio_user_dev *dev,
> arg = (void *)vm;
> }
>
> - if (req_kernel == VHOST_SET_FEATURES) {
> - /* We don't need memory protection here */
> - *(uint64_t *)arg &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM);
> -
> - /* VHOST kernel does not know about below flags */
> - *(uint64_t *)arg &= ~VHOST_KERNEL_GUEST_OFFLOADS_MASK;
> - *(uint64_t *)arg &= ~VHOST_KERNEL_HOST_OFFLOADS_MASK;
> -
> - *(uint64_t *)arg &= ~(1ULL << VIRTIO_NET_F_MQ);
> - }
> -
> switch (req_kernel) {
> case VHOST_SET_VRING_NUM:
> case VHOST_SET_VRING_ADDR:
> @@ -259,24 +271,6 @@ vhost_kernel_send_request(struct virtio_user_dev *dev,
> ret = ioctl(vhostfd, req_kernel, arg);
> }
>
> - if (!ret && req_kernel == VHOST_GET_FEATURES) {
> - features = tap_support_features();
> - /* with tap as the backend, all these features are supported
> - * but not claimed by vhost-net, so we add them back when
> - * reporting to upper layer.
> - */
> - if (features & IFF_VNET_HDR) {
> - *((uint64_t *)arg) |= VHOST_KERNEL_GUEST_OFFLOADS_MASK;
> - *((uint64_t *)arg) |= VHOST_KERNEL_HOST_OFFLOADS_MASK;
> - }
> -
> - /* vhost_kernel will not declare this feature, but it does
> - * support multi-queue.
> - */
> - if (features & IFF_MULTI_QUEUE)
> - *(uint64_t *)arg |= (1ull << VIRTIO_NET_F_MQ);
> - }
> -
> if (vm)
> free(vm);
>
> @@ -407,6 +401,8 @@ vhost_kernel_enable_queue_pair(struct virtio_user_dev
> *dev,
> struct virtio_user_backend_ops virtio_ops_kernel = {
> .setup = vhost_kernel_setup,
> .set_owner = vhost_kernel_set_owner,
> + .get_features = vhost_kernel_get_features,
> + .set_features = vhost_kernel_set_features,
> .send_request = vhost_kernel_send_request,
> .enable_qp = vhost_kernel_enable_queue_pair
> };
> diff --git a/drivers/net/virtio/virtio_user/vhost_kernel_tap.c
> b/drivers/net/virtio/virtio_user/vhost_kernel_tap.c
> index eade702c5c..99096bdf39 100644
> --- a/drivers/net/virtio/virtio_user/vhost_kernel_tap.c
> +++ b/drivers/net/virtio/virtio_user/vhost_kernel_tap.c
> @@ -18,6 +18,29 @@
> #include "../virtio_logs.h"
> #include "../virtio.h"
>
> +
> +int
> +tap_support_features(unsigned int *tap_features)
> +{
> + int tapfd;
> +
> + tapfd = open(PATH_NET_TUN, O_RDWR);
> + if (tapfd < 0) {
> + PMD_DRV_LOG(ERR, "fail to open %s: %s",
> + PATH_NET_TUN, strerror(errno));
> + return -1;
> + }
> +
> + if (ioctl(tapfd, TUNGETFEATURES, tap_features) == -1) {
> + PMD_DRV_LOG(ERR, "TUNGETFEATURES failed: %s", strerror(errno));
> + close(tapfd);
> + return -1;
> + }
> +
> + close(tapfd);
> + return 0;
> +}
> +
> int
> vhost_kernel_tap_set_offload(int fd, uint64_t features)
> {
> diff --git a/drivers/net/virtio/virtio_user/vhost_kernel_tap.h
> b/drivers/net/virtio/virtio_user/vhost_kernel_tap.h
> index 5c4447b296..ed03fce21e 100644
> --- a/drivers/net/virtio/virtio_user/vhost_kernel_tap.h
> +++ b/drivers/net/virtio/virtio_user/vhost_kernel_tap.h
> @@ -43,5 +43,6 @@ int vhost_kernel_open_tap(char **p_ifname, int hdr_size, int
> req_mq,
> const char *mac, uint64_t features);
> int vhost_kernel_tap_set_offload(int fd, uint64_t features);
> int vhost_kernel_tap_set_queue(int fd, bool attach);
> +int tap_support_features(unsigned int *tap_features);
>
> #endif
> diff --git a/drivers/net/virtio/virtio_user/vhost_user.c
> b/drivers/net/virtio/virtio_user/vhost_user.c
> index ea3bd4ca10..8e5bf332d6 100644
> --- a/drivers/net/virtio/virtio_user/vhost_user.c
> +++ b/drivers/net/virtio/virtio_user/vhost_user.c
> @@ -143,6 +143,64 @@ vhost_user_set_owner(struct virtio_user_dev *dev)
> return 0;
> }
>
> +static int
> +vhost_user_get_features(struct virtio_user_dev *dev, uint64_t *features)
> +{
> + int ret;
> + struct vhost_user_msg msg = {
> + .request = VHOST_USER_GET_FEATURES,
> + .flags = VHOST_USER_VERSION,
> + };
> +
> + ret = vhost_user_write(dev->vhostfd, &msg, NULL, 0);
> + if (ret < 0)
> + goto err;
> +
> + ret = vhost_user_read(dev->vhostfd, &msg);
> + if (ret < 0)
> + goto err;
> +
> + if (msg.request != VHOST_USER_GET_FEATURES) {
> + PMD_DRV_LOG(ERR, "Unexpected request type (%d)", msg.request);
> + goto err;
> + }
> +
> + if (msg.size != sizeof(*features)) {
> + PMD_DRV_LOG(ERR, "Unexpected payload size (%u)", msg.size);
> + goto err;
> + }
> +
> + *features = msg.payload.u64;
> +
> + return 0;
> +err:
> + PMD_DRV_LOG(ERR, "Failed to get backend features");
> +
> + return -1;
> +}
> +
> +static int
> +vhost_user_set_features(struct virtio_user_dev *dev, uint64_t features)
> +{
> + int ret;
> + struct vhost_user_msg msg = {
> + .request = VHOST_USER_SET_FEATURES,
> + .flags = VHOST_USER_VERSION,
> + .size = sizeof(features),
> + .payload.u64 = features,
> + };
> +
> + msg.payload.u64 |= dev->device_features & (1ULL <<
> VHOST_USER_F_PROTOCOL_FEATURES);
> +
> + ret = vhost_user_write(dev->vhostfd, &msg, NULL, 0);
> + if (ret < 0) {
> + PMD_DRV_LOG(ERR, "Failed to set features");
> + return -1;
> + }
> +
> + return 0;
> +}
> +
> struct walk_arg {
> struct vhost_memory *vm;
> int *fds;
> @@ -249,8 +307,6 @@ static struct vhost_user_msg m;
>
> const char * const vhost_msg_strings[] = {
> [VHOST_USER_RESET_OWNER] = "VHOST_RESET_OWNER",
> - [VHOST_USER_SET_FEATURES] = "VHOST_SET_FEATURES",
> - [VHOST_USER_GET_FEATURES] = "VHOST_GET_FEATURES",
> [VHOST_USER_SET_VRING_CALL] = "VHOST_SET_VRING_CALL",
> [VHOST_USER_SET_VRING_NUM] = "VHOST_SET_VRING_NUM",
> [VHOST_USER_SET_VRING_BASE] = "VHOST_SET_VRING_BASE",
> @@ -299,7 +355,6 @@ vhost_user_sock(struct virtio_user_dev *dev,
> (1ULL << VHOST_USER_PROTOCOL_F_STATUS))))
> return -ENOTSUP;
> /* Fallthrough */
> - case VHOST_USER_GET_FEATURES:
> case VHOST_USER_GET_PROTOCOL_FEATURES:
> need_reply = 1;
> break;
> @@ -398,7 +453,6 @@ vhost_user_sock(struct virtio_user_dev *dev,
> }
>
> switch (req) {
> - case VHOST_USER_GET_FEATURES:
> case VHOST_USER_GET_STATUS:
> case VHOST_USER_GET_PROTOCOL_FEATURES:
> if (msg.size != sizeof(m.payload.u64)) {
> @@ -536,6 +590,8 @@ vhost_user_enable_queue_pair(struct virtio_user_dev *dev,
> struct virtio_user_backend_ops virtio_ops_user = {
> .setup = vhost_user_setup,
> .set_owner = vhost_user_set_owner,
> + .get_features = vhost_user_get_features,
> + .set_features = vhost_user_set_features,
> .send_request = vhost_user_sock,
> .enable_qp = vhost_user_enable_queue_pair
> };
> diff --git a/drivers/net/virtio/virtio_user/vhost_vdpa.c
> b/drivers/net/virtio/virtio_user/vhost_vdpa.c
> index d9bc213e0d..22a329526a 100644
> --- a/drivers/net/virtio/virtio_user/vhost_vdpa.c
> +++ b/drivers/net/virtio/virtio_user/vhost_vdpa.c
> @@ -40,8 +40,6 @@
>
> static uint64_t vhost_req_user_to_vdpa[] = {
> [VHOST_USER_RESET_OWNER] = VHOST_RESET_OWNER,
> - [VHOST_USER_SET_FEATURES] = VHOST_SET_FEATURES,
> - [VHOST_USER_GET_FEATURES] = VHOST_GET_FEATURES,
> [VHOST_USER_SET_VRING_CALL] = VHOST_SET_VRING_CALL,
> [VHOST_USER_SET_VRING_NUM] = VHOST_SET_VRING_NUM,
> [VHOST_USER_SET_VRING_BASE] = VHOST_SET_VRING_BASE,
> @@ -107,6 +105,32 @@ vhost_vdpa_set_owner(struct virtio_user_dev *dev)
> return vhost_vdpa_ioctl(dev->vhostfd, VHOST_SET_OWNER, NULL);
> }
>
> +static int
> +vhost_vdpa_get_features(struct virtio_user_dev *dev, uint64_t *features)
> +{
> + int ret;
> +
> + ret = vhost_vdpa_ioctl(dev->vhostfd, VHOST_GET_FEATURES, features);
> + if (ret) {
> + PMD_DRV_LOG(ERR, "Failed to get features");
> + return -1;
> + }
> +
> + /* Multiqueue not supported for now */
> + *features &= ~(1ULL << VIRTIO_NET_F_MQ);
> +
> + return 0;
> +}
> +
> +static int
> +vhost_vdpa_set_features(struct virtio_user_dev *dev, uint64_t features)
> +{
> + /* WORKAROUND */
> + features |= 1ULL << VIRTIO_F_IOMMU_PLATFORM;
> +
> + return vhost_vdpa_ioctl(dev->vhostfd, VHOST_SET_FEATURES, &features);
> +}
> +
> static int
> vhost_vdpa_iotlb_batch_begin(struct virtio_user_dev *dev)
> {
> @@ -343,14 +367,6 @@ vhost_vdpa_send_request(struct virtio_user_dev *dev,
> if (req_vdpa == VHOST_SET_MEM_TABLE)
> return vhost_vdpa_dma_map_all(dev);
>
> - if (req_vdpa == VHOST_SET_FEATURES) {
> - /* WORKAROUND */
> - *(uint64_t *)arg |= 1ULL << VIRTIO_F_IOMMU_PLATFORM;
> -
> - /* Multiqueue not supported for now */
> - *(uint64_t *)arg &= ~(1ULL << VIRTIO_NET_F_MQ);
> - }
> -
> switch (req_vdpa) {
> case VHOST_SET_VRING_NUM:
> case VHOST_SET_VRING_ADDR:
> @@ -429,6 +445,8 @@ vhost_vdpa_enable_queue_pair(struct virtio_user_dev *dev,
> struct virtio_user_backend_ops virtio_ops_vdpa = {
> .setup = vhost_vdpa_setup,
> .set_owner = vhost_vdpa_set_owner,
> + .get_features = vhost_vdpa_get_features,
> + .set_features = vhost_vdpa_set_features,
> .send_request = vhost_vdpa_send_request,
> .enable_qp = vhost_vdpa_enable_queue_pair,
> .dma_map = vhost_vdpa_dma_map_batch,
> diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c
> b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> index f4b97d8489..1f3bbae663 100644
> --- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
> +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
> @@ -141,7 +141,7 @@ virtio_user_dev_set_features(struct virtio_user_dev *dev)
> /* Strip VIRTIO_NET_F_CTRL_VQ, as devices do not really need to know */
> features &= ~(1ull << VIRTIO_NET_F_CTRL_VQ);
> features &= ~(1ull << VIRTIO_NET_F_STATUS);
> - ret = dev->ops->send_request(dev, VHOST_USER_SET_FEATURES, &features);
> + ret = dev->ops->set_features(dev, features);
> if (ret < 0)
> goto error;
> PMD_DRV_LOG(INFO, "set features: %" PRIx64, features);
> @@ -496,8 +496,7 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char
> *path, int queues,
> return -1;
> }
>
> - if (dev->ops->send_request(dev, VHOST_USER_GET_FEATURES,
> - &dev->device_features) < 0) {
> + if (dev->ops->get_features(dev, &dev->device_features) < 0) {
> PMD_INIT_LOG(ERR, "get_features failed: %s",
> strerror(errno));
> return -1;
> diff --git a/drivers/net/virtio/virtio_user_ethdev.c
> b/drivers/net/virtio/virtio_user_ethdev.c
> index 91794b8645..56c379bc15 100644
> --- a/drivers/net/virtio/virtio_user_ethdev.c
> +++ b/drivers/net/virtio/virtio_user_ethdev.c
> @@ -85,8 +85,7 @@ virtio_user_server_reconnect(struct virtio_user_dev *dev)
>
> virtio_set_status(hw, VIRTIO_CONFIG_STATUS_DRIVER);
>
> - if (dev->ops->send_request(dev, VHOST_USER_GET_FEATURES,
> - &dev->device_features) < 0) {
> + if (dev->ops->get_features(dev, &dev->device_features) < 0) {
> PMD_INIT_LOG(ERR, "get_features failed: %s",
> strerror(errno));
> return -1;
> --
> 2.29.2
Reviewed-by: Chenbo Xia <chenbo....@intel.com>
