[Feature]add MT2731_MP2_MR2_SVN388 baseline version

Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/net/tipc/discover.c b/src/kernel/linux/v4.14/net/tipc/discover.c
new file mode 100644
index 0000000..02462d6
--- /dev/null
+++ b/src/kernel/linux/v4.14/net/tipc/discover.c
@@ -0,0 +1,336 @@
+/*
+ * net/tipc/discover.c
+ *
+ * Copyright (c) 2003-2006, 2014-2015, Ericsson AB
+ * Copyright (c) 2005-2006, 2010-2011, Wind River Systems
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core.h"
+#include "node.h"
+#include "discover.h"
+
+/* min delay during bearer start up */
+#define TIPC_LINK_REQ_INIT	msecs_to_jiffies(125)
+/* max delay if bearer has no links */
+#define TIPC_LINK_REQ_FAST	msecs_to_jiffies(1000)
+/* max delay if bearer has links */
+#define TIPC_LINK_REQ_SLOW	msecs_to_jiffies(60000)
+/* indicates no timer in use */
+#define TIPC_LINK_REQ_INACTIVE	0xffffffff
+
+/**
+ * struct tipc_link_req - information about an ongoing link setup request
+ * @bearer_id: identity of bearer issuing requests
+ * @net: network namespace instance
+ * @dest: destination address for request messages
+ * @domain: network domain to which links can be established
+ * @num_nodes: number of nodes currently discovered (i.e. with an active link)
+ * @lock: spinlock for controlling access to requests
+ * @buf: request message to be (repeatedly) sent
+ * @timer: timer governing period between requests
+ * @timer_intv: current interval between requests (in ms)
+ */
+struct tipc_link_req {
+	u32 bearer_id;
+	struct tipc_media_addr dest;
+	struct net *net;
+	u32 domain;
+	int num_nodes;
+	spinlock_t lock;
+	struct sk_buff *buf;
+	struct timer_list timer;
+	unsigned long timer_intv;
+};
+
+/**
+ * tipc_disc_init_msg - initialize a link setup message
+ * @net: the applicable net namespace
+ * @type: message type (request or response)
+ * @b: ptr to bearer issuing message
+ */
+static void tipc_disc_init_msg(struct net *net, struct sk_buff *buf, u32 type,
+			       struct tipc_bearer *b)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_msg *msg;
+	u32 dest_domain = b->domain;
+
+	msg = buf_msg(buf);
+	tipc_msg_init(tn->own_addr, msg, LINK_CONFIG, type,
+		      MAX_H_SIZE, dest_domain);
+	msg_set_non_seq(msg, 1);
+	msg_set_node_sig(msg, tn->random);
+	msg_set_node_capabilities(msg, TIPC_NODE_CAPABILITIES);
+	msg_set_dest_domain(msg, dest_domain);
+	msg_set_bc_netid(msg, tn->net_id);
+	b->media->addr2msg(msg_media_addr(msg), &b->addr);
+}
+
+/**
+ * disc_dupl_alert - issue node address duplication alert
+ * @b: pointer to bearer detecting duplication
+ * @node_addr: duplicated node address
+ * @media_addr: media address advertised by duplicated node
+ */
+static void disc_dupl_alert(struct tipc_bearer *b, u32 node_addr,
+			    struct tipc_media_addr *media_addr)
+{
+	char node_addr_str[16];
+	char media_addr_str[64];
+
+	tipc_addr_string_fill(node_addr_str, node_addr);
+	tipc_media_addr_printf(media_addr_str, sizeof(media_addr_str),
+			       media_addr);
+	pr_warn("Duplicate %s using %s seen on <%s>\n", node_addr_str,
+		media_addr_str, b->name);
+}
+
+/**
+ * tipc_disc_rcv - handle incoming discovery message (request or response)
+ * @net: the applicable net namespace
+ * @buf: buffer containing message
+ * @bearer: bearer that message arrived on
+ */
+void tipc_disc_rcv(struct net *net, struct sk_buff *skb,
+		   struct tipc_bearer *bearer)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_media_addr maddr;
+	struct sk_buff *rskb;
+	struct tipc_msg *hdr = buf_msg(skb);
+	u32 ddom = msg_dest_domain(hdr);
+	u32 onode = msg_prevnode(hdr);
+	u32 net_id = msg_bc_netid(hdr);
+	u32 mtyp = msg_type(hdr);
+	u32 signature = msg_node_sig(hdr);
+	u16 caps = msg_node_capabilities(hdr);
+	bool respond = false;
+	bool dupl_addr = false;
+	int err;
+
+	err = bearer->media->msg2addr(bearer, &maddr, msg_media_addr(hdr));
+	kfree_skb(skb);
+	if (err)
+		return;
+
+	/* Ensure message from node is valid and communication is permitted */
+	if (net_id != tn->net_id)
+		return;
+	if (maddr.broadcast)
+		return;
+	if (!tipc_addr_domain_valid(ddom))
+		return;
+	if (!tipc_addr_node_valid(onode))
+		return;
+
+	if (in_own_node(net, onode)) {
+		if (memcmp(&maddr, &bearer->addr, sizeof(maddr)))
+			disc_dupl_alert(bearer, tn->own_addr, &maddr);
+		return;
+	}
+	if (!tipc_in_scope(ddom, tn->own_addr))
+		return;
+	if (!tipc_in_scope(bearer->domain, onode))
+		return;
+
+	tipc_node_check_dest(net, onode, bearer, caps, signature,
+			     &maddr, &respond, &dupl_addr);
+	if (dupl_addr)
+		disc_dupl_alert(bearer, onode, &maddr);
+
+	/* Send response, if necessary */
+	if (respond && (mtyp == DSC_REQ_MSG)) {
+		rskb = tipc_buf_acquire(MAX_H_SIZE, GFP_ATOMIC);
+		if (!rskb)
+			return;
+		tipc_disc_init_msg(net, rskb, DSC_RESP_MSG, bearer);
+		tipc_bearer_xmit_skb(net, bearer->identity, rskb, &maddr);
+	}
+}
+
+/**
+ * disc_update - update frequency of periodic link setup requests
+ * @req: ptr to link request structure
+ *
+ * Reinitiates discovery process if discovery object has no associated nodes
+ * and is either not currently searching or is searching at a slow rate
+ */
+static void disc_update(struct tipc_link_req *req)
+{
+	if (!req->num_nodes) {
+		if ((req->timer_intv == TIPC_LINK_REQ_INACTIVE) ||
+		    (req->timer_intv > TIPC_LINK_REQ_FAST)) {
+			req->timer_intv = TIPC_LINK_REQ_INIT;
+			mod_timer(&req->timer, jiffies + req->timer_intv);
+		}
+	}
+}
+
+/**
+ * tipc_disc_add_dest - increment set of discovered nodes
+ * @req: ptr to link request structure
+ */
+void tipc_disc_add_dest(struct tipc_link_req *req)
+{
+	spin_lock_bh(&req->lock);
+	req->num_nodes++;
+	spin_unlock_bh(&req->lock);
+}
+
+/**
+ * tipc_disc_remove_dest - decrement set of discovered nodes
+ * @req: ptr to link request structure
+ */
+void tipc_disc_remove_dest(struct tipc_link_req *req)
+{
+	spin_lock_bh(&req->lock);
+	req->num_nodes--;
+	disc_update(req);
+	spin_unlock_bh(&req->lock);
+}
+
+/**
+ * disc_timeout - send a periodic link setup request
+ * @data: ptr to link request structure
+ *
+ * Called whenever a link setup request timer associated with a bearer expires.
+ */
+static void disc_timeout(unsigned long data)
+{
+	struct tipc_link_req *req = (struct tipc_link_req *)data;
+	struct sk_buff *skb;
+	int max_delay;
+
+	spin_lock_bh(&req->lock);
+
+	/* Stop searching if only desired node has been found */
+	if (tipc_node(req->domain) && req->num_nodes) {
+		req->timer_intv = TIPC_LINK_REQ_INACTIVE;
+		goto exit;
+	}
+
+	/*
+	 * Send discovery message, then update discovery timer
+	 *
+	 * Keep doubling time between requests until limit is reached;
+	 * hold at fast polling rate if don't have any associated nodes,
+	 * otherwise hold at slow polling rate
+	 */
+	skb = skb_clone(req->buf, GFP_ATOMIC);
+	if (skb)
+		tipc_bearer_xmit_skb(req->net, req->bearer_id, skb, &req->dest);
+	req->timer_intv *= 2;
+	if (req->num_nodes)
+		max_delay = TIPC_LINK_REQ_SLOW;
+	else
+		max_delay = TIPC_LINK_REQ_FAST;
+	if (req->timer_intv > max_delay)
+		req->timer_intv = max_delay;
+
+	mod_timer(&req->timer, jiffies + req->timer_intv);
+exit:
+	spin_unlock_bh(&req->lock);
+}
+
+/**
+ * tipc_disc_create - create object to send periodic link setup requests
+ * @net: the applicable net namespace
+ * @b: ptr to bearer issuing requests
+ * @dest: destination address for request messages
+ * @dest_domain: network domain to which links can be established
+ *
+ * Returns 0 if successful, otherwise -errno.
+ */
+int tipc_disc_create(struct net *net, struct tipc_bearer *b,
+		     struct tipc_media_addr *dest, struct sk_buff **skb)
+{
+	struct tipc_link_req *req;
+
+	req = kmalloc(sizeof(*req), GFP_ATOMIC);
+	if (!req)
+		return -ENOMEM;
+	req->buf = tipc_buf_acquire(MAX_H_SIZE, GFP_ATOMIC);
+	if (!req->buf) {
+		kfree(req);
+		return -ENOMEM;
+	}
+
+	tipc_disc_init_msg(net, req->buf, DSC_REQ_MSG, b);
+	memcpy(&req->dest, dest, sizeof(*dest));
+	req->net = net;
+	req->bearer_id = b->identity;
+	req->domain = b->domain;
+	req->num_nodes = 0;
+	req->timer_intv = TIPC_LINK_REQ_INIT;
+	spin_lock_init(&req->lock);
+	setup_timer(&req->timer, disc_timeout, (unsigned long)req);
+	mod_timer(&req->timer, jiffies + req->timer_intv);
+	b->link_req = req;
+	*skb = skb_clone(req->buf, GFP_ATOMIC);
+	return 0;
+}
+
+/**
+ * tipc_disc_delete - destroy object sending periodic link setup requests
+ * @req: ptr to link request structure
+ */
+void tipc_disc_delete(struct tipc_link_req *req)
+{
+	del_timer_sync(&req->timer);
+	kfree_skb(req->buf);
+	kfree(req);
+}
+
+/**
+ * tipc_disc_reset - reset object to send periodic link setup requests
+ * @net: the applicable net namespace
+ * @b: ptr to bearer issuing requests
+ * @dest_domain: network domain to which links can be established
+ */
+void tipc_disc_reset(struct net *net, struct tipc_bearer *b)
+{
+	struct tipc_link_req *req = b->link_req;
+	struct sk_buff *skb;
+
+	spin_lock_bh(&req->lock);
+	tipc_disc_init_msg(net, req->buf, DSC_REQ_MSG, b);
+	req->net = net;
+	req->bearer_id = b->identity;
+	req->domain = b->domain;
+	req->num_nodes = 0;
+	req->timer_intv = TIPC_LINK_REQ_INIT;
+	mod_timer(&req->timer, jiffies + req->timer_intv);
+	skb = skb_clone(req->buf, GFP_ATOMIC);
+	if (skb)
+		tipc_bearer_xmit_skb(net, req->bearer_id, skb, &req->dest);
+	spin_unlock_bh(&req->lock);
+}