[2/2] vhost: refactor to follow new naming convention

diff --git a/drivers/vdpa/ifc/ifcvf_vdpa.c b/drivers/vdpa/ifc/ifcvf_vdpa.c
index fe4d278c5380..e4133568c1aa 100644
--- a/drivers/vdpa/ifc/ifcvf_vdpa.c
+++ b/drivers/vdpa/ifc/ifcvf_vdpa.c
@@ -605,7 +605,7 @@  virtio_interrupt_handler(struct ifcvf_internal *internal)
 	int vid = internal->vid;
 	int ret;
 
-	ret = rte_vhost_slave_config_change(vid, 1);
+	ret = rte_vhost_backend_config_change(vid, 1);
 	if (ret)
 		DRV_LOG(ERR, "failed to notify the guest about configuration space change.");
 }
diff --git a/lib/vhost/rte_vhost.h b/lib/vhost/rte_vhost.h
index ed255fc6c51f..cc2ec99c315c 100644
--- a/lib/vhost/rte_vhost.h
+++ b/lib/vhost/rte_vhost.h
@@ -1066,7 +1066,7 @@  rte_vhost_get_vdpa_device(int vid);
  */
 __rte_experimental
 int
-rte_vhost_slave_config_change(int vid, bool need_reply);
+rte_vhost_backend_config_change(int vid, bool need_reply);
 
 /**
  * Retrieve names of statistics of a Vhost virtqueue.
diff --git a/lib/vhost/version.map b/lib/vhost/version.map
index d779a5cf3a0a..d322a4a888cd 100644
--- a/lib/vhost/version.map
+++ b/lib/vhost/version.map
@@ -68,7 +68,7 @@  EXPERIMENTAL {
 	global:
 
 	rte_vhost_crypto_driver_start;
-	rte_vhost_slave_config_change;
+	rte_vhost_backend_config_change;
 	rte_vhost_async_channel_register;
 	rte_vhost_async_channel_unregister;
 	rte_vhost_submit_enqueue_burst;
diff --git a/lib/vhost/vhost.c b/lib/vhost/vhost.c
index 358672bb176b..ef3794381751 100644
--- a/lib/vhost/vhost.c
+++ b/lib/vhost/vhost.c
@@ -701,9 +701,9 @@  vhost_new_device(void)
 
 	dev->vid = i;
 	dev->flags = VIRTIO_DEV_BUILTIN_VIRTIO_NET;
-	dev->slave_req_fd = -1;
+	dev->backend_req_fd = -1;
 	dev->postcopy_ufd = -1;
-	rte_spinlock_init(&dev->slave_req_lock);
+	rte_spinlock_init(&dev->backend_req_lock);
 
 	return i;
 }
diff --git a/lib/vhost/vhost.h b/lib/vhost/vhost.h
index a31d810531d7..8fdab13c7097 100644
--- a/lib/vhost/vhost.h
+++ b/lib/vhost/vhost.h
@@ -499,8 +499,8 @@  struct virtio_net {
 	uint32_t		max_guest_pages;
 	struct guest_page       *guest_pages;
 
-	int			slave_req_fd;
-	rte_spinlock_t		slave_req_lock;
+	int			backend_req_fd;
+	rte_spinlock_t		backend_req_lock;
 
 	int			postcopy_ufd;
 	int			postcopy_listening;
diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c
index cd4104ea5ce0..1ce1a5924f74 100644
--- a/lib/vhost/vhost_user.c
+++ b/lib/vhost/vhost_user.c
@@ -226,9 +226,9 @@  vhost_backend_cleanup(struct virtio_net *dev)
 		dev->inflight_info = NULL;
 	}
 
-	if (dev->slave_req_fd >= 0) {
-		close(dev->slave_req_fd);
-		dev->slave_req_fd = -1;
+	if (dev->backend_req_fd >= 0) {
+		close(dev->backend_req_fd);
+		dev->backend_req_fd = -1;
 	}
 
 	if (dev->postcopy_ufd >= 0) {
@@ -2257,11 +2257,11 @@  vhost_user_set_protocol_features(struct virtio_net **pdev,
 {
 	struct virtio_net *dev = *pdev;
 	uint64_t protocol_features = ctx->msg.payload.u64;
-	uint64_t slave_protocol_features = 0;
+	uint64_t backend_protocol_features = 0;
 
 	rte_vhost_driver_get_protocol_features(dev->ifname,
-			&slave_protocol_features);
-	if (protocol_features & ~slave_protocol_features) {
+			&backend_protocol_features);
+	if (protocol_features & ~backend_protocol_features) {
 		VHOST_LOG_CONFIG(dev->ifname, ERR, "received invalid protocol features.\n");
 		return RTE_VHOST_MSG_RESULT_ERR;
 	}
@@ -2458,14 +2458,14 @@  vhost_user_set_req_fd(struct virtio_net **pdev,
 
 	if (fd < 0) {
 		VHOST_LOG_CONFIG(dev->ifname, ERR,
-			"invalid file descriptor for slave channel (%d)\n", fd);
+			"invalid file descriptor for backend channel (%d)\n", fd);
 		return RTE_VHOST_MSG_RESULT_ERR;
 	}
 
-	if (dev->slave_req_fd >= 0)
-		close(dev->slave_req_fd);
+	if (dev->backend_req_fd >= 0)
+		close(dev->backend_req_fd);
 
-	dev->slave_req_fd = fd;
+	dev->backend_req_fd = fd;
 
 	return RTE_VHOST_MSG_RESULT_OK;
 }
@@ -2931,46 +2931,46 @@  send_vhost_reply(struct virtio_net *dev, int sockfd, struct vhu_msg_context *ctx
 }
 
 static int
-send_vhost_slave_message(struct virtio_net *dev, struct vhu_msg_context *ctx)
+send_vhost_backend_message(struct virtio_net *dev, struct vhu_msg_context *ctx)
 {
-	return send_vhost_message(dev, dev->slave_req_fd, ctx);
+	return send_vhost_message(dev, dev->backend_req_fd, ctx);
 }
 
 static int
-send_vhost_slave_message_process_reply(struct virtio_net *dev, struct vhu_msg_context *ctx)
+send_vhost_backend_message_process_reply(struct virtio_net *dev, struct vhu_msg_context *ctx)
 {
 	struct vhu_msg_context msg_reply;
 	int ret;
 
-	rte_spinlock_lock(&dev->slave_req_lock);
-	ret = send_vhost_slave_message(dev, ctx);
+	rte_spinlock_lock(&dev->backend_req_lock);
+	ret = send_vhost_backend_message(dev, ctx);
 	if (ret < 0) {
 		VHOST_LOG_CONFIG(dev->ifname, ERR, "failed to send config change (%d)\n", ret);
 		goto out;
 	}
 
-	ret = read_vhost_message(dev, dev->slave_req_fd, &msg_reply);
+	ret = read_vhost_message(dev, dev->backend_req_fd, &msg_reply);
 	if (ret <= 0) {
 		if (ret < 0)
 			VHOST_LOG_CONFIG(dev->ifname, ERR,
-				"vhost read slave message reply failed\n");
+				"vhost read backend message reply failed\n");
 		else
 			VHOST_LOG_CONFIG(dev->ifname, INFO, "vhost peer closed\n");
 		ret = -1;
 		goto out;
 	}
 
-	if (msg_reply.msg.request.slave != ctx->msg.request.slave) {
+	if (msg_reply.msg.request.backend != ctx->msg.request.backend) {
 		VHOST_LOG_CONFIG(dev->ifname, ERR,
 			"received unexpected msg type (%u), expected %u\n",
-			msg_reply.msg.request.slave, ctx->msg.request.slave);
+			msg_reply.msg.request.backend, ctx->msg.request.backend);
 		ret = -1;
 		goto out;
 	}
 
 	ret = msg_reply.msg.payload.u64 ? -1 : 0;
 out:
-	rte_spinlock_unlock(&dev->slave_req_lock);
+	rte_spinlock_unlock(&dev->backend_req_lock);
 	return ret;
 }
 
@@ -3307,7 +3307,7 @@  vhost_user_iotlb_miss(struct virtio_net *dev, uint64_t iova, uint8_t perm)
 	int ret;
 	struct vhu_msg_context ctx = {
 		.msg = {
-			.request.slave = VHOST_USER_BACKEND_IOTLB_MSG,
+			.request.backend = VHOST_USER_BACKEND_IOTLB_MSG,
 			.flags = VHOST_USER_VERSION,
 			.size = sizeof(ctx.msg.payload.iotlb),
 			.payload.iotlb = {
@@ -3318,7 +3318,7 @@  vhost_user_iotlb_miss(struct virtio_net *dev, uint64_t iova, uint8_t perm)
 		},
 	};
 
-	ret = send_vhost_message(dev, dev->slave_req_fd, &ctx);
+	ret = send_vhost_message(dev, dev->backend_req_fd, &ctx);
 	if (ret < 0) {
 		VHOST_LOG_CONFIG(dev->ifname, ERR,
 			"failed to send IOTLB miss message (%d)\n",
@@ -3330,11 +3330,11 @@  vhost_user_iotlb_miss(struct virtio_net *dev, uint64_t iova, uint8_t perm)
 }
 
 int
-rte_vhost_slave_config_change(int vid, bool need_reply)
+rte_vhost_backend_config_change(int vid, bool need_reply)
 {
 	struct vhu_msg_context ctx = {
 		.msg = {
-			.request.slave = VHOST_USER_BACKEND_CONFIG_CHANGE_MSG,
+			.request.backend = VHOST_USER_BACKEND_CONFIG_CHANGE_MSG,
 			.flags = VHOST_USER_VERSION,
 			.size = 0,
 		}
@@ -3347,10 +3347,10 @@  rte_vhost_slave_config_change(int vid, bool need_reply)
 		return -ENODEV;
 
 	if (!need_reply) {
-		ret = send_vhost_slave_message(dev, &ctx);
+		ret = send_vhost_backend_message(dev, &ctx);
 	} else {
 		ctx.msg.flags |= VHOST_USER_NEED_REPLY;
-		ret = send_vhost_slave_message_process_reply(dev, &ctx);
+		ret = send_vhost_backend_message_process_reply(dev, &ctx);
 	}
 
 	if (ret < 0)
@@ -3358,7 +3358,7 @@  rte_vhost_slave_config_change(int vid, bool need_reply)
 	return ret;
 }
 
-static int vhost_user_slave_set_vring_host_notifier(struct virtio_net *dev,
+static int vhost_user_backend_set_vring_host_notifier(struct virtio_net *dev,
 						    int index, int fd,
 						    uint64_t offset,
 						    uint64_t size)
@@ -3366,7 +3366,7 @@  static int vhost_user_slave_set_vring_host_notifier(struct virtio_net *dev,
 	int ret;
 	struct vhu_msg_context ctx = {
 		.msg = {
-			.request.slave = VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG,
+			.request.backend = VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG,
 			.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY,
 			.size = sizeof(ctx.msg.payload.area),
 			.payload.area = {
@@ -3384,7 +3384,7 @@  static int vhost_user_slave_set_vring_host_notifier(struct virtio_net *dev,
 		ctx.fd_num = 1;
 	}
 
-	ret = send_vhost_slave_message_process_reply(dev, &ctx);
+	ret = send_vhost_backend_message_process_reply(dev, &ctx);
 	if (ret < 0)
 		VHOST_LOG_CONFIG(dev->ifname, ERR, "failed to set host notifier (%d)\n", ret);
 
@@ -3444,7 +3444,7 @@  int rte_vhost_host_notifier_ctrl(int vid, uint16_t qid, bool enable)
 				goto disable;
 			}
 
-			if (vhost_user_slave_set_vring_host_notifier(dev, i,
+			if (vhost_user_backend_set_vring_host_notifier(dev, i,
 					vfio_device_fd, offset, size) < 0) {
 				ret = -EFAULT;
 				goto disable;
@@ -3453,7 +3453,7 @@  int rte_vhost_host_notifier_ctrl(int vid, uint16_t qid, bool enable)
 	} else {
 disable:
 		for (i = q_start; i <= q_last; i++) {
-			vhost_user_slave_set_vring_host_notifier(dev, i, -1,
+			vhost_user_backend_set_vring_host_notifier(dev, i, -1,
 					0, 0);
 		}
 	}
diff --git a/lib/vhost/vhost_user.h b/lib/vhost/vhost_user.h
index 8e418414ba94..cd8610129789 100644
--- a/lib/vhost/vhost_user.h
+++ b/lib/vhost/vhost_user.h
@@ -62,12 +62,12 @@  typedef enum VhostUserRequest {
 	VHOST_USER_GET_STATUS = 40,
 } VhostUserRequest;
 
-typedef enum VhostUserSlaveRequest {
+typedef enum VhostUserBackendRequest {
 	VHOST_USER_BACKEND_NONE = 0,
 	VHOST_USER_BACKEND_IOTLB_MSG = 1,
 	VHOST_USER_BACKEND_CONFIG_CHANGE_MSG = 2,
 	VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG = 3,
-} VhostUserSlaveRequest;
+} VhostUserBackendRequest;
 
 typedef struct VhostUserMemoryRegion {
 	uint64_t guest_phys_addr;
@@ -137,7 +137,7 @@  struct vhost_user_config {
 typedef struct VhostUserMsg {
 	union {
 		uint32_t master; /* a VhostUserRequest value */
-		uint32_t slave;  /* a VhostUserSlaveRequest value*/
+		uint32_t backend;  /* a VhostUserBackendRequest value*/
 	} request;
 
 #define VHOST_USER_VERSION_MASK     0x3