[dpdk-dev] [PATCH] kni: Add link status update

[Vijayakumar Muthuvel Manickam]

Add an ioctl command in rte_kni module to enable
DPDK applications to propagate link state changes to
kni virtual interfaces.

Signed-off-by: Vijayakumar Muthuvel Manickam <mmvijay at gmail.com>
---
 .../linuxapp/eal/include/exec-env/rte_kni_common.h |  2 ++
 lib/librte_eal/linuxapp/kni/kni_misc.c             | 39 ++++++++++++++++++++++
 lib/librte_kni/rte_kni.c                           | 18 ++++++++++
 lib/librte_kni/rte_kni.h                           | 17 ++++++++++
 4 files changed, 76 insertions(+)

diff --git a/lib/librte_eal/linuxapp/eal/include/exec-env/rte_kni_common.h b/lib/librte_eal/linuxapp/eal/include/exec-env/rte_kni_common.h
index 1e55c2d..b68001d 100644
--- a/lib/librte_eal/linuxapp/eal/include/exec-env/rte_kni_common.h
+++ b/lib/librte_eal/linuxapp/eal/include/exec-env/rte_kni_common.h
@@ -163,6 +163,7 @@ struct rte_kni_device_info {
 
 	/* mbuf size */
 	unsigned mbuf_size;
+	uint8_t link_state;
 };
 
 #define KNI_DEVICE "kni"
@@ -170,5 +171,6 @@ struct rte_kni_device_info {
 #define RTE_KNI_IOCTL_TEST    _IOWR(0, 1, int)
 #define RTE_KNI_IOCTL_CREATE  _IOWR(0, 2, struct rte_kni_device_info)
 #define RTE_KNI_IOCTL_RELEASE _IOWR(0, 3, struct rte_kni_device_info)
+#define RTE_KNI_IOCTL_LINK_UPDATE _IOWR(0, 4, struct rte_kni_device_info)
 
 #endif /* _RTE_KNI_COMMON_H_ */
diff --git a/lib/librte_eal/linuxapp/kni/kni_misc.c b/lib/librte_eal/linuxapp/kni/kni_misc.c
index 1935d32..b1015cd 100644
--- a/lib/librte_eal/linuxapp/kni/kni_misc.c
+++ b/lib/librte_eal/linuxapp/kni/kni_misc.c
@@ -548,6 +548,42 @@ kni_ioctl_release(unsigned int ioctl_num, unsigned long ioctl_param)
 }
 
 static int
+kni_ioctl_update_link_state(unsigned int ioctl_num, unsigned long ioctl_param)
+{
+	int ret = -EINVAL;
+	struct kni_dev *dev, *n;
+	struct rte_kni_device_info dev_info;
+
+	if (_IOC_SIZE(ioctl_num) > sizeof(dev_info))
+			return -EINVAL;
+
+	ret = copy_from_user(&dev_info, (void *)ioctl_param, sizeof(dev_info));
+	if (ret) {
+		KNI_ERR("copy_from_user in kni_ioctl_update_link_status");
+		return -EIO;
+	}
+
+	if (strlen(dev_info.name) == 0)
+		return ret;
+
+	down_write(&kni_list_lock);
+	list_for_each_entry_safe(dev, n, &kni_list_head, list) {
+		if (strncmp(dev->name, dev_info.name, RTE_KNI_NAMESIZE) != 0)
+			continue;
+
+		if (dev_info.link_state == 0)
+			netif_carrier_off(dev->net_dev);
+		else
+			netif_carrier_on(dev->net_dev);
+		ret = 0;
+		break;
+	}
+	up_write(&kni_list_lock);
+
+	return ret;
+}
+
+static int
 kni_ioctl(struct inode *inode,
 	unsigned int ioctl_num,
 	unsigned long ioctl_param)
@@ -569,6 +605,9 @@ kni_ioctl(struct inode *inode,
 	case _IOC_NR(RTE_KNI_IOCTL_RELEASE):
 		ret = kni_ioctl_release(ioctl_num, ioctl_param);
 		break;
+	case _IOC_NR(RTE_KNI_IOCTL_LINK_UPDATE):
+		ret = kni_ioctl_update_link_state(ioctl_num, ioctl_param);
+		break;
 	default:
 		KNI_DBG("IOCTL default \n");
 		break;
diff --git a/lib/librte_kni/rte_kni.c b/lib/librte_kni/rte_kni.c
index 4e70fa0..b6eda8a 100644
--- a/lib/librte_kni/rte_kni.c
+++ b/lib/librte_kni/rte_kni.c
@@ -512,6 +512,24 @@ rte_kni_release(struct rte_kni *kni)
 }
 
 int
+rte_kni_update_link_state(struct rte_kni *kni, uint8_t if_up)
+{
+	struct rte_kni_device_info dev_info;
+
+	if (!kni || !kni->in_use)
+		return -1;
+
+	snprintf(dev_info.name, sizeof(dev_info.name), "%s", kni->name);
+	dev_info.link_state = if_up;
+	if (ioctl(kni_fd, RTE_KNI_IOCTL_LINK_UPDATE, &dev_info) < 0) {
+		RTE_LOG(ERR, KNI, "Fail to update link state\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+int
 rte_kni_handle_request(struct rte_kni *kni)
 {
 	unsigned ret;
diff --git a/lib/librte_kni/rte_kni.h b/lib/librte_kni/rte_kni.h
index 98edd72..a1bafd9 100644
--- a/lib/librte_kni/rte_kni.h
+++ b/lib/librte_kni/rte_kni.h
@@ -167,6 +167,23 @@ extern struct rte_kni *rte_kni_create(uint8_t port_id,
 extern int rte_kni_release(struct rte_kni *kni);
 
 /**
+ * Send link state changes to KNI interface in kernel space
+ *
+ * rte_kni_update_link_state is thread safe.
+ *
+ * @param kni
+ *  The pointer to the context of an existent KNI interface.
+ * @param if_up
+ *  interface link status
+ *
+ * @return
+ *  - 0 indicates success.
+ *  - negative value indicates failure.
+ */
+
+extern int rte_kni_update_link_state(struct rte_kni *kni, uint8_t if_up);
+
+/**
  * It is used to handle the request mbufs sent from kernel space.
  * Then analyzes it and calls the specific actions for the specific requests.
  * Finally constructs the response mbuf and puts it back to the resp_q.
-- 
1.8.1.4