[dpdk-dev] [PATCH v2] vhost: provide vhost API to unregister vhost unix domain socket

[Huawei Xie <huawei.xie@intel.com>]

rte_vhost_driver_unregister will remove the listenfd from event list, and then close it.

Signed-off-by: Huawei Xie <huawei.xie@intel.com>
Signed-off-by: Peng Sun <peng.a.sun@intel.com>
---
 lib/librte_vhost/rte_virtio_net.h            |  3 ++
 lib/librte_vhost/vhost_cuse/vhost-net-cdev.c |  9 ++++
 lib/librte_vhost/vhost_user/vhost-net-user.c | 68 +++++++++++++++++++++++-----
 lib/librte_vhost/vhost_user/vhost-net-user.h |  2 +-
 4 files changed, 69 insertions(+), 13 deletions(-)

diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index 5d38185..5630fbc 100644
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -188,6 +188,9 @@ int rte_vhost_enable_guest_notification(struct virtio_net *dev, uint16_t queue_i
 /* Register vhost driver. dev_name could be different for multiple instance support. */
 int rte_vhost_driver_register(const char *dev_name);
 
+/* Unregister vhost driver. This is only meaningful to vhost user. */
+int rte_vhost_driver_unregister(const char *dev_name);
+
 /* Register callbacks. */
 int rte_vhost_driver_callback_register(struct virtio_net_device_ops const * const);
 /* Start vhost driver session blocking loop. */
diff --git a/lib/librte_vhost/vhost_cuse/vhost-net-cdev.c b/lib/librte_vhost/vhost_cuse/vhost-net-cdev.c
index 6b68abf..1ae7c49 100644
--- a/lib/librte_vhost/vhost_cuse/vhost-net-cdev.c
+++ b/lib/librte_vhost/vhost_cuse/vhost-net-cdev.c
@@ -405,6 +405,15 @@ rte_vhost_driver_register(const char *dev_name)
 }
 
 /**
+ * An empty function for unregister
+ */
+int
+rte_vhost_driver_unregister(const char *dev_name __rte_unused)
+{
+	return 0;
+}
+
+/**
  * The CUSE session is launched allowing the application to receive open,
  * release and ioctl calls.
  */
diff --git a/lib/librte_vhost/vhost_user/vhost-net-user.c b/lib/librte_vhost/vhost_user/vhost-net-user.c
index 31f1215..87a4711 100644
--- a/lib/librte_vhost/vhost_user/vhost-net-user.c
+++ b/lib/librte_vhost/vhost_user/vhost-net-user.c
@@ -66,6 +66,8 @@ struct connfd_ctx {
 struct _vhost_server {
 	struct vhost_server *server[MAX_VHOST_SERVER];
 	struct fdset fdset;
+	int vserver_cnt;
+	pthread_mutex_t server_mutex;
 };
 
 static struct _vhost_server g_vhost_server = {
@@ -74,10 +76,10 @@ static struct _vhost_server g_vhost_server = {
 		.fd_mutex = PTHREAD_MUTEX_INITIALIZER,
 		.num = 0
 	},
+	.vserver_cnt = 0,
+	.server_mutex = PTHREAD_MUTEX_INITIALIZER,
 };
 
-static int vserver_idx;
-
 static const char *vhost_message_str[VHOST_USER_MAX] = {
 	[VHOST_USER_NONE] = "VHOST_USER_NONE",
 	[VHOST_USER_GET_FEATURES] = "VHOST_USER_GET_FEATURES",
@@ -427,7 +429,6 @@ vserver_message_handler(int connfd, void *dat, int *remove)
 	}
 }
 
-
 /**
  * Creates and initialise the vhost server.
  */
@@ -436,34 +437,77 @@ rte_vhost_driver_register(const char *path)
 {
 	struct vhost_server *vserver;
 
-	if (vserver_idx == 0)
+	pthread_mutex_lock(&g_vhost_server.server_mutex);
+	if (ops == NULL)
 		ops = get_virtio_net_callbacks();
-	if (vserver_idx == MAX_VHOST_SERVER)
+
+	if (g_vhost_server.vserver_cnt == MAX_VHOST_SERVER) {
+		RTE_LOG(ERR, VHOST_CONFIG,
+			"error: the number of servers reaches maximum\n");
+		pthread_mutex_unlock(&g_vhost_server.server_mutex);
 		return -1;
+	}
 
 	vserver = calloc(sizeof(struct vhost_server), 1);
-	if (vserver == NULL)
+	if (vserver == NULL) {
+		pthread_mutex_unlock(&g_vhost_server.server_mutex);
 		return -1;
-
-	unlink(path);
+	}
 
 	vserver->listenfd = uds_socket(path);
 	if (vserver->listenfd < 0) {
 		free(vserver);
+		pthread_mutex_unlock(&g_vhost_server.server_mutex);
 		return -1;
 	}
-	vserver->path = path;
+
+	vserver->path = strdup(path);
 
 	fdset_add(&g_vhost_server.fdset, vserver->listenfd,
-		vserver_new_vq_conn, NULL,
-		vserver);
+		vserver_new_vq_conn, NULL, vserver);
 
-	g_vhost_server.server[vserver_idx++] = vserver;
+	g_vhost_server.server[g_vhost_server.vserver_cnt++] = vserver;
+	pthread_mutex_unlock(&g_vhost_server.server_mutex);
 
 	return 0;
 }
 
 
+/**
+ * Unregister the specified vhost server
+ */
+int
+rte_vhost_driver_unregister(const char *path)
+{
+	int i;
+	int count;
+
+	pthread_mutex_lock(&g_vhost_server.server_mutex);
+
+	for (i = 0; i < g_vhost_server.vserver_cnt; i++) {
+		if (!strcmp(g_vhost_server.server[i]->path, path)) {
+			fdset_del(&g_vhost_server.fdset,
+				g_vhost_server.server[i]->listenfd);
+
+			close(g_vhost_server.server[i]->listenfd);
+			free(g_vhost_server.server[i]->path);
+			free(g_vhost_server.server[i]);
+
+			unlink(path);
+
+			count = --g_vhost_server.vserver_cnt;
+			g_vhost_server.server[i] = g_vhost_server.server[count];
+			g_vhost_server.server[count] = NULL;
+			pthread_mutex_unlock(&g_vhost_server.server_mutex);
+
+			return 0;
+		}
+	}
+	pthread_mutex_unlock(&g_vhost_server.server_mutex);
+
+	return -1;
+}
+
 int
 rte_vhost_driver_session_start(void)
 {
diff --git a/lib/librte_vhost/vhost_user/vhost-net-user.h b/lib/librte_vhost/vhost_user/vhost-net-user.h
index 1b6be6c..2e72f3c 100644
--- a/lib/librte_vhost/vhost_user/vhost-net-user.h
+++ b/lib/librte_vhost/vhost_user/vhost-net-user.h
@@ -41,7 +41,7 @@
 #include "fd_man.h"
 
 struct vhost_server {
-	const char *path; /**< The path the uds is bind to. */
+	char *path; /**< The path the uds is bind to. */
 	int listenfd;     /**< The listener sockfd. */
 };
 
-- 
1.8.1.4