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Diffstat (limited to 'kernel/linux/kni/kni_net.c')
-rw-r--r--kernel/linux/kni/kni_net.c757
1 files changed, 757 insertions, 0 deletions
diff --git a/kernel/linux/kni/kni_net.c b/kernel/linux/kni/kni_net.c
new file mode 100644
index 0000000..9f9b798
--- /dev/null
+++ b/kernel/linux/kni/kni_net.c
@@ -0,0 +1,757 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright(c) 2010-2014 Intel Corporation.
+ */
+
+/*
+ * This code is inspired from the book "Linux Device Drivers" by
+ * Alessandro Rubini and Jonathan Corbet, published by O'Reilly & Associates
+ */
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h> /* eth_type_trans */
+#include <linux/skbuff.h>
+#include <linux/kthread.h>
+#include <linux/delay.h>
+
+#include <exec-env/rte_kni_common.h>
+#include <kni_fifo.h>
+
+#include "compat.h"
+#include "kni_dev.h"
+
+#define WD_TIMEOUT 5 /*jiffies */
+
+#define KNI_WAIT_RESPONSE_TIMEOUT 300 /* 3 seconds */
+
+/* typedef for rx function */
+typedef void (*kni_net_rx_t)(struct kni_dev *kni);
+
+static void kni_net_rx_normal(struct kni_dev *kni);
+
+/* kni rx function pointer, with default to normal rx */
+static kni_net_rx_t kni_net_rx_func = kni_net_rx_normal;
+
+/* physical address to kernel virtual address */
+static void *
+pa2kva(void *pa)
+{
+ return phys_to_virt((unsigned long)pa);
+}
+
+/* physical address to virtual address */
+static void *
+pa2va(void *pa, struct rte_kni_mbuf *m)
+{
+ void *va;
+
+ va = (void *)((unsigned long)pa +
+ (unsigned long)m->buf_addr -
+ (unsigned long)m->buf_physaddr);
+ return va;
+}
+
+/* mbuf data kernel virtual address from mbuf kernel virtual address */
+static void *
+kva2data_kva(struct rte_kni_mbuf *m)
+{
+ return phys_to_virt(m->buf_physaddr + m->data_off);
+}
+
+/* virtual address to physical address */
+static void *
+va2pa(void *va, struct rte_kni_mbuf *m)
+{
+ void *pa;
+
+ pa = (void *)((unsigned long)va -
+ ((unsigned long)m->buf_addr -
+ (unsigned long)m->buf_physaddr));
+ return pa;
+}
+
+/*
+ * It can be called to process the request.
+ */
+static int
+kni_net_process_request(struct kni_dev *kni, struct rte_kni_request *req)
+{
+ int ret = -1;
+ void *resp_va;
+ uint32_t num;
+ int ret_val;
+
+ if (!kni || !req) {
+ pr_err("No kni instance or request\n");
+ return -EINVAL;
+ }
+
+ mutex_lock(&kni->sync_lock);
+
+ /* Construct data */
+ memcpy(kni->sync_kva, req, sizeof(struct rte_kni_request));
+ num = kni_fifo_put(kni->req_q, &kni->sync_va, 1);
+ if (num < 1) {
+ pr_err("Cannot send to req_q\n");
+ ret = -EBUSY;
+ goto fail;
+ }
+
+ ret_val = wait_event_interruptible_timeout(kni->wq,
+ kni_fifo_count(kni->resp_q), 3 * HZ);
+ if (signal_pending(current) || ret_val <= 0) {
+ ret = -ETIME;
+ goto fail;
+ }
+ num = kni_fifo_get(kni->resp_q, (void **)&resp_va, 1);
+ if (num != 1 || resp_va != kni->sync_va) {
+ /* This should never happen */
+ pr_err("No data in resp_q\n");
+ ret = -ENODATA;
+ goto fail;
+ }
+
+ memcpy(req, kni->sync_kva, sizeof(struct rte_kni_request));
+ ret = 0;
+
+fail:
+ mutex_unlock(&kni->sync_lock);
+ return ret;
+}
+
+/*
+ * Open and close
+ */
+static int
+kni_net_open(struct net_device *dev)
+{
+ int ret;
+ struct rte_kni_request req;
+ struct kni_dev *kni = netdev_priv(dev);
+
+ netif_start_queue(dev);
+
+ memset(&req, 0, sizeof(req));
+ req.req_id = RTE_KNI_REQ_CFG_NETWORK_IF;
+
+ /* Setting if_up to non-zero means up */
+ req.if_up = 1;
+ ret = kni_net_process_request(kni, &req);
+
+ return (ret == 0) ? req.result : ret;
+}
+
+static int
+kni_net_release(struct net_device *dev)
+{
+ int ret;
+ struct rte_kni_request req;
+ struct kni_dev *kni = netdev_priv(dev);
+
+ netif_stop_queue(dev); /* can't transmit any more */
+
+ memset(&req, 0, sizeof(req));
+ req.req_id = RTE_KNI_REQ_CFG_NETWORK_IF;
+
+ /* Setting if_up to 0 means down */
+ req.if_up = 0;
+ ret = kni_net_process_request(kni, &req);
+
+ return (ret == 0) ? req.result : ret;
+}
+
+/*
+ * Configuration changes (passed on by ifconfig)
+ */
+static int
+kni_net_config(struct net_device *dev, struct ifmap *map)
+{
+ if (dev->flags & IFF_UP) /* can't act on a running interface */
+ return -EBUSY;
+
+ /* ignore other fields */
+ return 0;
+}
+
+/*
+ * Transmit a packet (called by the kernel)
+ */
+static int
+kni_net_tx(struct sk_buff *skb, struct net_device *dev)
+{
+ int len = 0;
+ uint32_t ret;
+ struct kni_dev *kni = netdev_priv(dev);
+ struct rte_kni_mbuf *pkt_kva = NULL;
+ void *pkt_pa = NULL;
+ void *pkt_va = NULL;
+
+ /* save the timestamp */
+#ifdef HAVE_TRANS_START_HELPER
+ netif_trans_update(dev);
+#else
+ dev->trans_start = jiffies;
+#endif
+
+ /* Check if the length of skb is less than mbuf size */
+ if (skb->len > kni->mbuf_size)
+ goto drop;
+
+ /**
+ * Check if it has at least one free entry in tx_q and
+ * one entry in alloc_q.
+ */
+ if (kni_fifo_free_count(kni->tx_q) == 0 ||
+ kni_fifo_count(kni->alloc_q) == 0) {
+ /**
+ * If no free entry in tx_q or no entry in alloc_q,
+ * drops skb and goes out.
+ */
+ goto drop;
+ }
+
+ /* dequeue a mbuf from alloc_q */
+ ret = kni_fifo_get(kni->alloc_q, &pkt_pa, 1);
+ if (likely(ret == 1)) {
+ void *data_kva;
+
+ pkt_kva = pa2kva(pkt_pa);
+ data_kva = kva2data_kva(pkt_kva);
+ pkt_va = pa2va(pkt_pa, pkt_kva);
+
+ len = skb->len;
+ memcpy(data_kva, skb->data, len);
+ if (unlikely(len < ETH_ZLEN)) {
+ memset(data_kva + len, 0, ETH_ZLEN - len);
+ len = ETH_ZLEN;
+ }
+ pkt_kva->pkt_len = len;
+ pkt_kva->data_len = len;
+
+ /* enqueue mbuf into tx_q */
+ ret = kni_fifo_put(kni->tx_q, &pkt_va, 1);
+ if (unlikely(ret != 1)) {
+ /* Failing should not happen */
+ pr_err("Fail to enqueue mbuf into tx_q\n");
+ goto drop;
+ }
+ } else {
+ /* Failing should not happen */
+ pr_err("Fail to dequeue mbuf from alloc_q\n");
+ goto drop;
+ }
+
+ /* Free skb and update statistics */
+ dev_kfree_skb(skb);
+ kni->stats.tx_bytes += len;
+ kni->stats.tx_packets++;
+
+ return NETDEV_TX_OK;
+
+drop:
+ /* Free skb and update statistics */
+ dev_kfree_skb(skb);
+ kni->stats.tx_dropped++;
+
+ return NETDEV_TX_OK;
+}
+
+/*
+ * RX: normal working mode
+ */
+static void
+kni_net_rx_normal(struct kni_dev *kni)
+{
+ uint32_t ret;
+ uint32_t len;
+ uint32_t i, num_rx, num_fq;
+ struct rte_kni_mbuf *kva;
+ void *data_kva;
+ struct sk_buff *skb;
+ struct net_device *dev = kni->net_dev;
+
+ /* Get the number of free entries in free_q */
+ num_fq = kni_fifo_free_count(kni->free_q);
+ if (num_fq == 0) {
+ /* No room on the free_q, bail out */
+ return;
+ }
+
+ /* Calculate the number of entries to dequeue from rx_q */
+ num_rx = min_t(uint32_t, num_fq, MBUF_BURST_SZ);
+
+ /* Burst dequeue from rx_q */
+ num_rx = kni_fifo_get(kni->rx_q, kni->pa, num_rx);
+ if (num_rx == 0)
+ return;
+
+ /* Transfer received packets to netif */
+ for (i = 0; i < num_rx; i++) {
+ kva = pa2kva(kni->pa[i]);
+ len = kva->pkt_len;
+ data_kva = kva2data_kva(kva);
+ kni->va[i] = pa2va(kni->pa[i], kva);
+
+ skb = dev_alloc_skb(len + 2);
+ if (!skb) {
+ /* Update statistics */
+ kni->stats.rx_dropped++;
+ continue;
+ }
+
+ /* Align IP on 16B boundary */
+ skb_reserve(skb, 2);
+
+ if (kva->nb_segs == 1) {
+ memcpy(skb_put(skb, len), data_kva, len);
+ } else {
+ int nb_segs;
+ int kva_nb_segs = kva->nb_segs;
+
+ for (nb_segs = 0; nb_segs < kva_nb_segs; nb_segs++) {
+ memcpy(skb_put(skb, kva->data_len),
+ data_kva, kva->data_len);
+
+ if (!kva->next)
+ break;
+
+ kva = pa2kva(va2pa(kva->next, kva));
+ data_kva = kva2data_kva(kva);
+ }
+ }
+
+ skb->dev = dev;
+ skb->protocol = eth_type_trans(skb, dev);
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+ /* Call netif interface */
+ netif_rx_ni(skb);
+
+ /* Update statistics */
+ kni->stats.rx_bytes += len;
+ kni->stats.rx_packets++;
+ }
+
+ /* Burst enqueue mbufs into free_q */
+ ret = kni_fifo_put(kni->free_q, kni->va, num_rx);
+ if (ret != num_rx)
+ /* Failing should not happen */
+ pr_err("Fail to enqueue entries into free_q\n");
+}
+
+/*
+ * RX: loopback with enqueue/dequeue fifos.
+ */
+static void
+kni_net_rx_lo_fifo(struct kni_dev *kni)
+{
+ uint32_t ret;
+ uint32_t len;
+ uint32_t i, num, num_rq, num_tq, num_aq, num_fq;
+ struct rte_kni_mbuf *kva;
+ void *data_kva;
+ struct rte_kni_mbuf *alloc_kva;
+ void *alloc_data_kva;
+
+ /* Get the number of entries in rx_q */
+ num_rq = kni_fifo_count(kni->rx_q);
+
+ /* Get the number of free entrie in tx_q */
+ num_tq = kni_fifo_free_count(kni->tx_q);
+
+ /* Get the number of entries in alloc_q */
+ num_aq = kni_fifo_count(kni->alloc_q);
+
+ /* Get the number of free entries in free_q */
+ num_fq = kni_fifo_free_count(kni->free_q);
+
+ /* Calculate the number of entries to be dequeued from rx_q */
+ num = min(num_rq, num_tq);
+ num = min(num, num_aq);
+ num = min(num, num_fq);
+ num = min_t(uint32_t, num, MBUF_BURST_SZ);
+
+ /* Return if no entry to dequeue from rx_q */
+ if (num == 0)
+ return;
+
+ /* Burst dequeue from rx_q */
+ ret = kni_fifo_get(kni->rx_q, kni->pa, num);
+ if (ret == 0)
+ return; /* Failing should not happen */
+
+ /* Dequeue entries from alloc_q */
+ ret = kni_fifo_get(kni->alloc_q, kni->alloc_pa, num);
+ if (ret) {
+ num = ret;
+ /* Copy mbufs */
+ for (i = 0; i < num; i++) {
+ kva = pa2kva(kni->pa[i]);
+ len = kva->pkt_len;
+ data_kva = kva2data_kva(kva);
+ kni->va[i] = pa2va(kni->pa[i], kva);
+
+ alloc_kva = pa2kva(kni->alloc_pa[i]);
+ alloc_data_kva = kva2data_kva(alloc_kva);
+ kni->alloc_va[i] = pa2va(kni->alloc_pa[i], alloc_kva);
+
+ memcpy(alloc_data_kva, data_kva, len);
+ alloc_kva->pkt_len = len;
+ alloc_kva->data_len = len;
+
+ kni->stats.tx_bytes += len;
+ kni->stats.rx_bytes += len;
+ }
+
+ /* Burst enqueue mbufs into tx_q */
+ ret = kni_fifo_put(kni->tx_q, kni->alloc_va, num);
+ if (ret != num)
+ /* Failing should not happen */
+ pr_err("Fail to enqueue mbufs into tx_q\n");
+ }
+
+ /* Burst enqueue mbufs into free_q */
+ ret = kni_fifo_put(kni->free_q, kni->va, num);
+ if (ret != num)
+ /* Failing should not happen */
+ pr_err("Fail to enqueue mbufs into free_q\n");
+
+ /**
+ * Update statistic, and enqueue/dequeue failure is impossible,
+ * as all queues are checked at first.
+ */
+ kni->stats.tx_packets += num;
+ kni->stats.rx_packets += num;
+}
+
+/*
+ * RX: loopback with enqueue/dequeue fifos and sk buffer copies.
+ */
+static void
+kni_net_rx_lo_fifo_skb(struct kni_dev *kni)
+{
+ uint32_t ret;
+ uint32_t len;
+ uint32_t i, num_rq, num_fq, num;
+ struct rte_kni_mbuf *kva;
+ void *data_kva;
+ struct sk_buff *skb;
+ struct net_device *dev = kni->net_dev;
+
+ /* Get the number of entries in rx_q */
+ num_rq = kni_fifo_count(kni->rx_q);
+
+ /* Get the number of free entries in free_q */
+ num_fq = kni_fifo_free_count(kni->free_q);
+
+ /* Calculate the number of entries to dequeue from rx_q */
+ num = min(num_rq, num_fq);
+ num = min_t(uint32_t, num, MBUF_BURST_SZ);
+
+ /* Return if no entry to dequeue from rx_q */
+ if (num == 0)
+ return;
+
+ /* Burst dequeue mbufs from rx_q */
+ ret = kni_fifo_get(kni->rx_q, kni->pa, num);
+ if (ret == 0)
+ return;
+
+ /* Copy mbufs to sk buffer and then call tx interface */
+ for (i = 0; i < num; i++) {
+ kva = pa2kva(kni->pa[i]);
+ len = kva->pkt_len;
+ data_kva = kva2data_kva(kva);
+ kni->va[i] = pa2va(kni->pa[i], kva);
+
+ skb = dev_alloc_skb(len + 2);
+ if (skb) {
+ /* Align IP on 16B boundary */
+ skb_reserve(skb, 2);
+ memcpy(skb_put(skb, len), data_kva, len);
+ skb->dev = dev;
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+ dev_kfree_skb(skb);
+ }
+
+ /* Simulate real usage, allocate/copy skb twice */
+ skb = dev_alloc_skb(len + 2);
+ if (skb == NULL) {
+ kni->stats.rx_dropped++;
+ continue;
+ }
+
+ /* Align IP on 16B boundary */
+ skb_reserve(skb, 2);
+
+ if (kva->nb_segs == 1) {
+ memcpy(skb_put(skb, len), data_kva, len);
+ } else {
+ int nb_segs;
+ int kva_nb_segs = kva->nb_segs;
+
+ for (nb_segs = 0; nb_segs < kva_nb_segs; nb_segs++) {
+ memcpy(skb_put(skb, kva->data_len),
+ data_kva, kva->data_len);
+
+ if (!kva->next)
+ break;
+
+ kva = pa2kva(va2pa(kva->next, kva));
+ data_kva = kva2data_kva(kva);
+ }
+ }
+
+ skb->dev = dev;
+ skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+ kni->stats.rx_bytes += len;
+ kni->stats.rx_packets++;
+
+ /* call tx interface */
+ kni_net_tx(skb, dev);
+ }
+
+ /* enqueue all the mbufs from rx_q into free_q */
+ ret = kni_fifo_put(kni->free_q, kni->va, num);
+ if (ret != num)
+ /* Failing should not happen */
+ pr_err("Fail to enqueue mbufs into free_q\n");
+}
+
+/* rx interface */
+void
+kni_net_rx(struct kni_dev *kni)
+{
+ /**
+ * It doesn't need to check if it is NULL pointer,
+ * as it has a default value
+ */
+ (*kni_net_rx_func)(kni);
+}
+
+/*
+ * Deal with a transmit timeout.
+ */
+static void
+kni_net_tx_timeout(struct net_device *dev)
+{
+ struct kni_dev *kni = netdev_priv(dev);
+
+ pr_debug("Transmit timeout at %ld, latency %ld\n", jiffies,
+ jiffies - dev_trans_start(dev));
+
+ kni->stats.tx_errors++;
+ netif_wake_queue(dev);
+}
+
+/*
+ * Ioctl commands
+ */
+static int
+kni_net_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+ pr_debug("kni_net_ioctl group:%d cmd:%d\n",
+ ((struct kni_dev *)netdev_priv(dev))->group_id, cmd);
+
+ return 0;
+}
+
+static void
+kni_net_set_rx_mode(struct net_device *dev)
+{
+}
+
+static int
+kni_net_change_mtu(struct net_device *dev, int new_mtu)
+{
+ int ret;
+ struct rte_kni_request req;
+ struct kni_dev *kni = netdev_priv(dev);
+
+ pr_debug("kni_net_change_mtu new mtu %d to be set\n", new_mtu);
+
+ memset(&req, 0, sizeof(req));
+ req.req_id = RTE_KNI_REQ_CHANGE_MTU;
+ req.new_mtu = new_mtu;
+ ret = kni_net_process_request(kni, &req);
+ if (ret == 0 && req.result == 0)
+ dev->mtu = new_mtu;
+
+ return (ret == 0) ? req.result : ret;
+}
+
+static void
+kni_net_set_promiscusity(struct net_device *netdev, int flags)
+{
+ struct rte_kni_request req;
+ struct kni_dev *kni = netdev_priv(netdev);
+
+ memset(&req, 0, sizeof(req));
+ req.req_id = RTE_KNI_REQ_CHANGE_PROMISC;
+
+ if (netdev->flags & IFF_PROMISC)
+ req.promiscusity = 1;
+ else
+ req.promiscusity = 0;
+ kni_net_process_request(kni, &req);
+}
+
+/*
+ * Checks if the user space application provided the resp message
+ */
+void
+kni_net_poll_resp(struct kni_dev *kni)
+{
+ if (kni_fifo_count(kni->resp_q))
+ wake_up_interruptible(&kni->wq);
+}
+
+/*
+ * Return statistics to the caller
+ */
+static struct net_device_stats *
+kni_net_stats(struct net_device *dev)
+{
+ struct kni_dev *kni = netdev_priv(dev);
+
+ return &kni->stats;
+}
+
+/*
+ * Fill the eth header
+ */
+static int
+kni_net_header(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type, const void *daddr,
+ const void *saddr, uint32_t len)
+{
+ struct ethhdr *eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
+
+ memcpy(eth->h_source, saddr ? saddr : dev->dev_addr, dev->addr_len);
+ memcpy(eth->h_dest, daddr ? daddr : dev->dev_addr, dev->addr_len);
+ eth->h_proto = htons(type);
+
+ return dev->hard_header_len;
+}
+
+/*
+ * Re-fill the eth header
+ */
+#ifdef HAVE_REBUILD_HEADER
+static int
+kni_net_rebuild_header(struct sk_buff *skb)
+{
+ struct net_device *dev = skb->dev;
+ struct ethhdr *eth = (struct ethhdr *) skb->data;
+
+ memcpy(eth->h_source, dev->dev_addr, dev->addr_len);
+ memcpy(eth->h_dest, dev->dev_addr, dev->addr_len);
+
+ return 0;
+}
+#endif /* < 4.1.0 */
+
+/**
+ * kni_net_set_mac - Change the Ethernet Address of the KNI NIC
+ * @netdev: network interface device structure
+ * @p: pointer to an address structure
+ *
+ * Returns 0 on success, negative on failure
+ **/
+static int
+kni_net_set_mac(struct net_device *netdev, void *p)
+{
+ int ret;
+ struct rte_kni_request req;
+ struct kni_dev *kni;
+ struct sockaddr *addr = p;
+
+ memset(&req, 0, sizeof(req));
+ req.req_id = RTE_KNI_REQ_CHANGE_MAC_ADDR;
+
+ if (!is_valid_ether_addr((unsigned char *)(addr->sa_data)))
+ return -EADDRNOTAVAIL;
+
+ memcpy(req.mac_addr, addr->sa_data, netdev->addr_len);
+ memcpy(netdev->dev_addr, addr->sa_data, netdev->addr_len);
+
+ kni = netdev_priv(netdev);
+ ret = kni_net_process_request(kni, &req);
+
+ return (ret == 0 ? req.result : ret);
+}
+
+#ifdef HAVE_CHANGE_CARRIER_CB
+static int
+kni_net_change_carrier(struct net_device *dev, bool new_carrier)
+{
+ if (new_carrier)
+ netif_carrier_on(dev);
+ else
+ netif_carrier_off(dev);
+ return 0;
+}
+#endif
+
+static const struct header_ops kni_net_header_ops = {
+ .create = kni_net_header,
+#ifdef HAVE_REBUILD_HEADER
+ .rebuild = kni_net_rebuild_header,
+#endif /* < 4.1.0 */
+ .cache = NULL, /* disable caching */
+};
+
+static const struct net_device_ops kni_net_netdev_ops = {
+ .ndo_open = kni_net_open,
+ .ndo_stop = kni_net_release,
+ .ndo_set_config = kni_net_config,
+ .ndo_change_rx_flags = kni_net_set_promiscusity,
+ .ndo_start_xmit = kni_net_tx,
+ .ndo_change_mtu = kni_net_change_mtu,
+ .ndo_do_ioctl = kni_net_ioctl,
+ .ndo_set_rx_mode = kni_net_set_rx_mode,
+ .ndo_get_stats = kni_net_stats,
+ .ndo_tx_timeout = kni_net_tx_timeout,
+ .ndo_set_mac_address = kni_net_set_mac,
+#ifdef HAVE_CHANGE_CARRIER_CB
+ .ndo_change_carrier = kni_net_change_carrier,
+#endif
+};
+
+void
+kni_net_init(struct net_device *dev)
+{
+ struct kni_dev *kni = netdev_priv(dev);
+
+ init_waitqueue_head(&kni->wq);
+ mutex_init(&kni->sync_lock);
+
+ ether_setup(dev); /* assign some of the fields */
+ dev->netdev_ops = &kni_net_netdev_ops;
+ dev->header_ops = &kni_net_header_ops;
+ dev->watchdog_timeo = WD_TIMEOUT;
+}
+
+void
+kni_net_config_lo_mode(char *lo_str)
+{
+ if (!lo_str) {
+ pr_debug("loopback disabled");
+ return;
+ }
+
+ if (!strcmp(lo_str, "lo_mode_none"))
+ pr_debug("loopback disabled");
+ else if (!strcmp(lo_str, "lo_mode_fifo")) {
+ pr_debug("loopback mode=lo_mode_fifo enabled");
+ kni_net_rx_func = kni_net_rx_lo_fifo;
+ } else if (!strcmp(lo_str, "lo_mode_fifo_skb")) {
+ pr_debug("loopback mode=lo_mode_fifo_skb enabled");
+ kni_net_rx_func = kni_net_rx_lo_fifo_skb;
+ } else
+ pr_debug("Incognizant parameter, loopback disabled");
+}