net/virtio: move backend type selection to ethdev

This is a preparation patch with no functional change.

Use an enum instead of a boolean for the backend type.
Move the detection logic to the ethdev layer (where it is needed for the
first time).
The virtio_user_dev stores the backend type in the virtio_user_dev
struct so the type is only determined once

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Signed-off-by: Adrian Moreno <amorenoz@redhat.com>
Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>

diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c b/drivers/net/virtio/virtio_user/virtio_user_dev.c
index 2a0c861..b79a9f8 100644 (file)
--- a/drivers/net/virtio/virtio_user/virtio_user_dev.c
+++ b/drivers/net/virtio/virtio_user/virtio_user_dev.c
@@ -111,17 +111,6 @@ virtio_user_queue_setup(struct virtio_user_dev *dev,
        return 0;
 }
 
-int
-is_vhost_user_by_type(const char *path)
-{
-       struct stat sb;
-
-       if (stat(path, &sb) == -1)
-               return 0;
-
-       return S_ISSOCK(sb.st_mode);
-}
-
 int
 virtio_user_start_device(struct virtio_user_dev *dev)
 {
@@ -144,7 +133,8 @@ virtio_user_start_device(struct virtio_user_dev *dev)
        rte_mcfg_mem_read_lock();
        pthread_mutex_lock(&dev->mutex);
 
-       if (is_vhost_user_by_type(dev->path) && dev->vhostfd < 0)
+       if (dev->backend_type == VIRTIO_USER_BACKEND_VHOST_USER &&
+                       dev->vhostfd < 0)
                goto error;
 
        /* Step 0: tell vhost to create queues */
@@ -360,16 +350,16 @@ virtio_user_dev_setup(struct virtio_user_dev *dev)
        dev->tapfds = NULL;
 
        if (dev->is_server) {
-               if (access(dev->path, F_OK) == 0 &&
-                   !is_vhost_user_by_type(dev->path)) {
-                       PMD_DRV_LOG(ERR, "Server mode doesn't support vhost-kernel!");
+               if (dev->backend_type != VIRTIO_USER_BACKEND_VHOST_USER) {
+                       PMD_DRV_LOG(ERR, "Server mode only supports vhost-user!");
                        return -1;
                }
                dev->ops = &virtio_ops_user;
        } else {
-               if (is_vhost_user_by_type(dev->path)) {
+               if (dev->backend_type == VIRTIO_USER_BACKEND_VHOST_USER) {
                        dev->ops = &virtio_ops_user;
-               } else {
+               } else if (dev->backend_type ==
+                                       VIRTIO_USER_BACKEND_VHOST_KERNEL) {
                        dev->ops = &virtio_ops_kernel;
 
                        dev->vhostfds = malloc(dev->max_queue_pairs *
@@ -430,7 +420,8 @@ virtio_user_dev_setup(struct virtio_user_dev *dev)
 int
 virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
                     int cq, int queue_size, const char *mac, char **ifname,
-                    int server, int mrg_rxbuf, int in_order, int packed_vq)
+                    int server, int mrg_rxbuf, int in_order, int packed_vq,
+                    enum virtio_user_backend_type backend_type)
 {
        uint64_t protocol_features = 0;
 
@@ -445,6 +436,8 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
        dev->frontend_features = 0;
        dev->unsupported_features = ~VIRTIO_USER_SUPPORTED_FEATURES;
        dev->protocol_features = VIRTIO_USER_SUPPORTED_PROTOCOL_FEATURES;
+       dev->backend_type = backend_type;
+
        parse_mac(dev, mac);
 
        if (*ifname) {
@@ -457,7 +450,7 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
                return -1;
        }
 
-       if (!is_vhost_user_by_type(dev->path))
+       if (dev->backend_type != VIRTIO_USER_BACKEND_VHOST_USER)
                dev->unsupported_features |=
                        (1ULL << VHOST_USER_F_PROTOCOL_FEATURES);
 
@@ -539,7 +532,7 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
        }
 
        /* The backend will not report this feature, we add it explicitly */
-       if (is_vhost_user_by_type(dev->path))
+       if (dev->backend_type == VIRTIO_USER_BACKEND_VHOST_USER)
                dev->frontend_features |= (1ull << VIRTIO_NET_F_STATUS);
 
        /*
@@ -792,7 +785,7 @@ virtio_user_send_status_update(struct virtio_user_dev *dev, uint8_t status)
        uint64_t arg = status;
 
        /* Vhost-user only for now */
-       if (!is_vhost_user_by_type(dev->path))
+       if (dev->backend_type != VIRTIO_USER_BACKEND_VHOST_USER)
                return 0;
 
        if (!(dev->protocol_features & (1ULL << VHOST_USER_PROTOCOL_F_STATUS)))
@@ -815,7 +808,7 @@ virtio_user_update_status(struct virtio_user_dev *dev)
        int err;
 
        /* Vhost-user only for now */
-       if (!is_vhost_user_by_type(dev->path))
+       if (dev->backend_type != VIRTIO_USER_BACKEND_VHOST_USER)
                return 0;
 
        if (!(dev->protocol_features & (1UL << VHOST_USER_PROTOCOL_F_STATUS)))

diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.h b/drivers/net/virtio/virtio_user/virtio_user_dev.h
index 9377d5b..575bf43 100644 (file)
--- a/drivers/net/virtio/virtio_user/virtio_user_dev.h
+++ b/drivers/net/virtio/virtio_user/virtio_user_dev.h
@@ -10,6 +10,12 @@
 #include "../virtio_pci.h"
 #include "../virtio_ring.h"
 
+enum virtio_user_backend_type {
+       VIRTIO_USER_BACKEND_UNKNOWN,
+       VIRTIO_USER_BACKEND_VHOST_USER,
+       VIRTIO_USER_BACKEND_VHOST_KERNEL,
+};
+
 struct virtio_user_queue {
        uint16_t used_idx;
        bool avail_wrap_counter;
@@ -17,6 +23,7 @@ struct virtio_user_queue {
 };
 
 struct virtio_user_dev {
+       enum virtio_user_backend_type backend_type;
        /* for vhost_user backend */
        int             vhostfd;
        int             listenfd;   /* listening fd */
@@ -60,13 +67,13 @@ struct virtio_user_dev {
        bool            started;
 };
 
-int is_vhost_user_by_type(const char *path);
 int virtio_user_start_device(struct virtio_user_dev *dev);
 int virtio_user_stop_device(struct virtio_user_dev *dev);
 int virtio_user_dev_init(struct virtio_user_dev *dev, char *path, int queues,
                         int cq, int queue_size, const char *mac, char **ifname,
                         int server, int mrg_rxbuf, int in_order,
-                        int packed_vq);
+                        int packed_vq,
+                        enum virtio_user_backend_type backend_type);
 void virtio_user_dev_uninit(struct virtio_user_dev *dev);
 void virtio_user_handle_cq(struct virtio_user_dev *dev, uint16_t queue_idx);
 void virtio_user_handle_cq_packed(struct virtio_user_dev *dev,

diff --git a/drivers/net/virtio/virtio_user_ethdev.c b/drivers/net/virtio/virtio_user_ethdev.c
index 60d17af..38b49ba 100644 (file)
--- a/drivers/net/virtio/virtio_user_ethdev.c
+++ b/drivers/net/virtio/virtio_user_ethdev.c
@@ -6,6 +6,7 @@
 #include <sys/types.h>
 #include <unistd.h>
 #include <fcntl.h>
+#include <sys/stat.h>
 #include <sys/socket.h>
 
 #include <rte_malloc.h>
@@ -518,6 +519,19 @@ get_integer_arg(const char *key __rte_unused,
        return -errno;
 }
 
+static enum virtio_user_backend_type
+virtio_user_backend_type(const char *path)
+{
+       struct stat sb;
+
+       if (stat(path, &sb) == -1)
+               return VIRTIO_USER_BACKEND_UNKNOWN;
+
+       return S_ISSOCK(sb.st_mode) ?
+               VIRTIO_USER_BACKEND_VHOST_USER :
+               VIRTIO_USER_BACKEND_VHOST_KERNEL;
+}
+
 static struct rte_eth_dev *
 virtio_user_eth_dev_alloc(struct rte_vdev_device *vdev)
 {
@@ -579,6 +593,7 @@ virtio_user_pmd_probe(struct rte_vdev_device *dev)
        struct rte_kvargs *kvlist = NULL;
        struct rte_eth_dev *eth_dev;
        struct virtio_hw *hw;
+       enum virtio_user_backend_type backend_type = VIRTIO_USER_BACKEND_UNKNOWN;
        uint64_t queues = VIRTIO_USER_DEF_Q_NUM;
        uint64_t cq = VIRTIO_USER_DEF_CQ_EN;
        uint64_t queue_size = VIRTIO_USER_DEF_Q_SZ;
@@ -631,8 +646,17 @@ virtio_user_pmd_probe(struct rte_vdev_device *dev)
                goto end;
        }
 
+       backend_type = virtio_user_backend_type(path);
+       if (backend_type == VIRTIO_USER_BACKEND_UNKNOWN) {
+               PMD_INIT_LOG(ERR,
+                            "unable to determine backend type for path %s",
+                       path);
+               goto end;
+       }
+
+
        if (rte_kvargs_count(kvlist, VIRTIO_USER_ARG_INTERFACE_NAME) == 1) {
-               if (is_vhost_user_by_type(path)) {
+               if (backend_type != VIRTIO_USER_BACKEND_VHOST_KERNEL) {
                        PMD_INIT_LOG(ERR,
                                "arg %s applies only to vhost-kernel backend",
                                VIRTIO_USER_ARG_INTERFACE_NAME);
@@ -751,7 +775,7 @@ virtio_user_pmd_probe(struct rte_vdev_device *dev)
        hw = eth_dev->data->dev_private;
        if (virtio_user_dev_init(hw->virtio_user_dev, path, queues, cq,
                         queue_size, mac_addr, &ifname, server_mode,
-                        mrg_rxbuf, in_order, packed_vq) < 0) {
+                        mrg_rxbuf, in_order, packed_vq, backend_type) < 0) {
                PMD_INIT_LOG(ERR, "virtio_user_dev_init fails");
                virtio_user_eth_dev_free(eth_dev);
                goto end;