[v2,3/8] net/virtio: move backend type selection to ethdev

Message ID 20200925123113.68916-4-maxime.coquelin@redhat.com (mailing list archive)
State Superseded, archived
Delegated to: Maxime Coquelin
Headers
Series virtio-user: introduce vhost-vdpa backend |

Checks

Context Check Description
ci/checkpatch warning coding style issues

Commit Message

Maxime Coquelin Sept. 25, 2020, 12:31 p.m. UTC
  From: Adrian Moreno <amorenoz@redhat.com>

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>
---
 .../net/virtio/virtio_user/virtio_user_dev.c  | 37 ++++++++-----------
 .../net/virtio/virtio_user/virtio_user_dev.h  | 11 +++++-
 drivers/net/virtio/virtio_user_ethdev.c       | 28 +++++++++++++-
 3 files changed, 50 insertions(+), 26 deletions(-)
  

Patch

diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.c b/drivers/net/virtio/virtio_user/virtio_user_dev.c
index 2a0c861085..7cb93b1b33 100644
--- 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 9377d5ba66..575bf430c0 100644
--- 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 60d17af888..7bf065f34b 100644
--- 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;