1 files changed, 318 insertions, 0 deletions

diff --git a/net/tipc/discover.c b/net/tipc/discover.c
new file mode 100644
index 000000000000..b106ef1621cc
--- /dev/null
+++ b/net/tipc/discover.c
@@ -0,0 +1,318 @@
+/*
+ * net/tipc/discover.c
+ * 
+ * Copyright (c) 2003-2006, Ericsson AB
+ * Copyright (c) 2005, 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 "dbg.h"
+#include "link.h"
+#include "zone.h"
+#include "discover.h"
+#include "port.h"
+#include "name_table.h"
+
+#define TIPC_LINK_REQ_INIT	125	/* min delay during bearer start up */
+#define TIPC_LINK_REQ_FAST	2000	/* normal delay if bearer has no links */
+#define TIPC_LINK_REQ_SLOW	600000	/* normal delay if bearer has links */
+
+#if 0
+#define  GET_NODE_INFO         300
+#define  GET_NODE_INFO_RESULT  301
+#define  FORWARD_LINK_PROBE    302
+#define  LINK_REQUEST_REJECTED 303
+#define  LINK_REQUEST_ACCEPTED 304
+#define  DROP_LINK_REQUEST     305
+#define  CHECK_LINK_COUNT      306
+#endif
+
+/* 
+ * TODO: Most of the inter-cluster setup stuff should be
+ * rewritten, and be made conformant with specification.
+ */ 
+
+
+/**
+ * struct link_req - information about an ongoing link setup request
+ * @bearer: bearer issuing requests
+ * @dest: destination address for request messages
+ * @buf: request message to be (repeatedly) sent
+ * @timer: timer governing period between requests
+ * @timer_intv: current interval between requests (in ms)
+ */
+struct link_req {
+	struct bearer *bearer;
+	struct tipc_media_addr dest;
+	struct sk_buff *buf;
+	struct timer_list timer;
+	unsigned int timer_intv;
+};
+
+
+#if 0
+int disc_create_link(const struct tipc_link_create *argv) 
+{
+	/* 
+	 * Code for inter cluster link setup here 
+	 */
+	return TIPC_OK;
+}
+#endif
+
+/*
+ * disc_lost_link(): A link has lost contact
+ */
+
+void disc_link_event(u32 addr, char *name, int up) 
+{
+	if (in_own_cluster(addr))
+		return;
+	/* 
+	 * Code for inter cluster link setup here 
+	 */
+}
+
+/** 
+ * disc_init_msg - initialize a link setup message
+ * @type: message type (request or response)
+ * @req_links: number of links associated with message
+ * @dest_domain: network domain of node(s) which should respond to message
+ * @b_ptr: ptr to bearer issuing message
+ */
+
+struct sk_buff *disc_init_msg(u32 type,
+			      u32 req_links,
+			      u32 dest_domain,
+			      struct bearer *b_ptr)
+{
+	struct sk_buff *buf = buf_acquire(DSC_H_SIZE);
+	struct tipc_msg *msg;
+
+	if (buf) {
+		msg = buf_msg(buf);
+		msg_init(msg, LINK_CONFIG, type, TIPC_OK, DSC_H_SIZE,
+			 dest_domain);
+		msg_set_non_seq(msg);
+		msg_set_req_links(msg, req_links);
+		msg_set_dest_domain(msg, dest_domain);
+		msg_set_bc_netid(msg, tipc_net_id);
+		msg_set_media_addr(msg, &b_ptr->publ.addr);
+	}
+	return buf;
+}
+
+/**
+ * disc_recv_msg - handle incoming link setup message (request or response)
+ * @buf: buffer containing message
+ */
+
+void disc_recv_msg(struct sk_buff *buf)
+{
+	struct bearer *b_ptr = (struct bearer *)TIPC_SKB_CB(buf)->handle;
+	struct link *link;
+	struct tipc_media_addr media_addr;
+	struct tipc_msg *msg = buf_msg(buf);
+	u32 dest = msg_dest_domain(msg);
+	u32 orig = msg_prevnode(msg);
+	u32 net_id = msg_bc_netid(msg);
+	u32 type = msg_type(msg);
+
+	msg_get_media_addr(msg,&media_addr);
+	msg_dbg(msg, "RECV:");
+	buf_discard(buf);
+
+	if (net_id != tipc_net_id)
+		return;
+	if (!addr_domain_valid(dest))
+		return;
+	if (!addr_node_valid(orig))
+		return;
+	if (orig == tipc_own_addr)
+		return;
+	if (!in_scope(dest, tipc_own_addr))
+		return;
+	if (is_slave(tipc_own_addr) && is_slave(orig))
+		return;
+	if (is_slave(orig) && !in_own_cluster(orig))
+		return;
+	if (in_own_cluster(orig)) {
+		/* Always accept link here */
+		struct sk_buff *rbuf;
+		struct tipc_media_addr *addr;
+		struct node *n_ptr = node_find(orig);
+		int link_up;
+		dbg(" in own cluster\n");
+		if (n_ptr == NULL) {
+			n_ptr = node_create(orig);
+		}
+		if (n_ptr == NULL) {
+			warn("Memory squeeze; Failed to create node\n");
+			return;
+		}
+		spin_lock_bh(&n_ptr->lock);
+		link = n_ptr->links[b_ptr->identity];
+		if (!link) {
+			dbg("creating link\n");
+			link = link_create(b_ptr, orig, &media_addr);
+			if (!link) {
+				spin_unlock_bh(&n_ptr->lock);                
+				return;
+			}
+		}
+		addr = &link->media_addr;
+		if (memcmp(addr, &media_addr, sizeof(*addr))) {
+			char addr_string[16];
+
+			warn("New bearer address for %s\n", 
+			     addr_string_fill(addr_string, orig));
+			memcpy(addr, &media_addr, sizeof(*addr));
+			link_reset(link);     
+		}
+		link_up = link_is_up(link);
+		spin_unlock_bh(&n_ptr->lock);                
+		if ((type == DSC_RESP_MSG) || link_up)
+			return;
+		rbuf = disc_init_msg(DSC_RESP_MSG, 1, orig, b_ptr);
+		if (rbuf != NULL) {
+			msg_dbg(buf_msg(rbuf),"SEND:");
+			b_ptr->media->send_msg(rbuf, &b_ptr->publ, &media_addr);
+			buf_discard(rbuf);
+		}
+	}
+}
+
+/**
+ * disc_stop_link_req - stop sending periodic link setup requests
+ * @req: ptr to link request structure
+ */
+
+void disc_stop_link_req(struct link_req *req) 
+{
+	if (!req)
+		return;
+		
+	k_cancel_timer(&req->timer);
+	k_term_timer(&req->timer);
+	buf_discard(req->buf);
+	kfree(req);
+} 
+
+/**
+ * disc_update_link_req - update frequency of periodic link setup requests
+ * @req: ptr to link request structure
+ */
+
+void disc_update_link_req(struct link_req *req) 
+{
+	if (!req)
+		return;
+
+	if (req->timer_intv == TIPC_LINK_REQ_SLOW) {
+		if (!req->bearer->nodes.count) {
+			req->timer_intv = TIPC_LINK_REQ_FAST;
+			k_start_timer(&req->timer, req->timer_intv);
+		}
+	} else if (req->timer_intv == TIPC_LINK_REQ_FAST) {
+		if (req->bearer->nodes.count) {
+			req->timer_intv = TIPC_LINK_REQ_SLOW;
+			k_start_timer(&req->timer, req->timer_intv);
+		}
+	} else {
+		/* leave timer "as is" if haven't yet reached a "normal" rate */
+	}
+} 
+
+/**
+ * disc_timeout - send a periodic link setup request
+ * @req: ptr to link request structure
+ * 
+ * Called whenever a link setup request timer associated with a bearer expires.
+ */
+
+static void disc_timeout(struct link_req *req) 
+{
+	spin_lock_bh(&req->bearer->publ.lock);
+
+	req->bearer->media->send_msg(req->buf, &req->bearer->publ, &req->dest);
+
+	if ((req->timer_intv == TIPC_LINK_REQ_SLOW) ||
+	    (req->timer_intv == TIPC_LINK_REQ_FAST)) {
+		/* leave timer interval "as is" if already at a "normal" rate */
+	} else {
+		req->timer_intv *= 2;
+		if (req->timer_intv > TIPC_LINK_REQ_SLOW)
+			req->timer_intv = TIPC_LINK_REQ_SLOW;
+		if ((req->timer_intv == TIPC_LINK_REQ_FAST) && 
+		    (req->bearer->nodes.count))
+			req->timer_intv = TIPC_LINK_REQ_SLOW;
+	}
+	k_start_timer(&req->timer, req->timer_intv);
+
+	spin_unlock_bh(&req->bearer->publ.lock);
+}
+
+/**
+ * disc_init_link_req - start sending periodic link setup requests
+ * @b_ptr: ptr to bearer issuing requests
+ * @dest: destination address for request messages
+ * @dest_domain: network domain of node(s) which should respond to message
+ * @req_links: max number of desired links
+ * 
+ * Returns pointer to link request structure, or NULL if unable to create.
+ */
+
+struct link_req *disc_init_link_req(struct bearer *b_ptr, 
+				    const struct tipc_media_addr *dest,
+				    u32 dest_domain,
+				    u32 req_links) 
+{
+	struct link_req *req;
+
+	req = (struct link_req *)kmalloc(sizeof(*req), GFP_ATOMIC);
+	if (!req)
+		return NULL;
+
+	req->buf = disc_init_msg(DSC_REQ_MSG, req_links, dest_domain, b_ptr);
+	if (!req->buf) {
+		kfree(req);
+		return NULL;
+	}
+
+	memcpy(&req->dest, dest, sizeof(*dest));
+	req->bearer = b_ptr;
+	req->timer_intv = TIPC_LINK_REQ_INIT;
+	k_init_timer(&req->timer, (Handler)disc_timeout, (unsigned long)req);
+	k_start_timer(&req->timer, req->timer_intv);
+	return req;
+} 
+