net/tipc/discover.c - linux/kernel/git/gregkh/char-misc - Git at Google

 /*
  * net/tipc/discover.c
  *
  * Copyright (c) 2003-2006, Ericsson AB
  * Copyright (c) 2005-2006, 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 tipc_disc_link_event(u32 addr, char *name, int up)
 {
 	if (in_own_cluster(addr))
 		return;
 	/*
 	 * Code for inter cluster link setup here
 	 */
 }

 /**
  * tipc_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
  */

 static struct sk_buff *tipc_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;
 }

 /**
  * tipc_disc_recv_msg - handle incoming link setup message (request or response)
  * @buf: buffer containing message
  */

 void tipc_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 (!tipc_addr_domain_valid(dest))
 		return;
 	if (!tipc_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 = tipc_node_find(orig);
 		int link_up;
 		dbg(" in own cluster\n");
 		if (n_ptr == NULL) {
 			n_ptr = tipc_node_create(orig);
 		}
 		if (n_ptr == NULL) {
 			return;
 		}
 		spin_lock_bh(&n_ptr->lock);
 		link = n_ptr->links[b_ptr->identity];
 		if (!link) {
 			dbg("creating link\n");
 			link = tipc_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))) {
 			warn("Resetting link <%s>, peer interface address changed\n",
 			     link->name);
 			memcpy(addr, &media_addr, sizeof(*addr));
 			tipc_link_reset(link);
 		}
 		link_up = tipc_link_is_up(link);
 		spin_unlock_bh(&n_ptr->lock);
 		if ((type == DSC_RESP_MSG) || link_up)
 			return;
 		rbuf = tipc_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);
 		}
 	}
 }

 /**
  * tipc_disc_stop_link_req - stop sending periodic link setup requests
  * @req: ptr to link request structure
  */

 void tipc_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);
 }

 /**
  * tipc_disc_update_link_req - update frequency of periodic link setup requests
  * @req: ptr to link request structure
  */

 void tipc_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_FAST)
 			req->timer_intv = TIPC_LINK_REQ_FAST;
 		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);
 }

 /**
  * tipc_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 *tipc_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 = kmalloc(sizeof(*req), GFP_ATOMIC);
 	if (!req)
 		return NULL;

 	req->buf = tipc_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;
 }
	/*
	* net/tipc/discover.c
	*
	* Copyright (c) 2003-2006, Ericsson AB
	* Copyright (c) 2005-2006, 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 tipc_disc_link_event(u32 addr, char *name, int up)
	{
	if (in_own_cluster(addr))
	return;
	/*
	* Code for inter cluster link setup here
	*/
	}

	/**
	* tipc_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
	*/

	static struct sk_buff *tipc_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;
	}

	/**
	* tipc_disc_recv_msg - handle incoming link setup message (request or response)
	* @buf: buffer containing message
	*/

	void tipc_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 (!tipc_addr_domain_valid(dest))
	return;
	if (!tipc_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 = tipc_node_find(orig);
	int link_up;
	dbg(" in own cluster\n");
	if (n_ptr == NULL) {
	n_ptr = tipc_node_create(orig);
	}
	if (n_ptr == NULL) {
	return;
	}
	spin_lock_bh(&n_ptr->lock);
	link = n_ptr->links[b_ptr->identity];
	if (!link) {
	dbg("creating link\n");
	link = tipc_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))) {
	warn("Resetting link <%s>, peer interface address changed\n",
	link->name);
	memcpy(addr, &media_addr, sizeof(*addr));
	tipc_link_reset(link);
	}
	link_up = tipc_link_is_up(link);
	spin_unlock_bh(&n_ptr->lock);
	if ((type == DSC_RESP_MSG) \|\| link_up)
	return;
	rbuf = tipc_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);
	}
	}
	}

	/**
	* tipc_disc_stop_link_req - stop sending periodic link setup requests
	* @req: ptr to link request structure
	*/

	void tipc_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);
	}

	/**
	* tipc_disc_update_link_req - update frequency of periodic link setup requests
	* @req: ptr to link request structure
	*/

	void tipc_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_FAST)
	req->timer_intv = TIPC_LINK_REQ_FAST;
	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);
	}

	/**
	* tipc_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 tipc_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 = kmalloc(sizeof(*req), GFP_ATOMIC);
	if (!req)
	return NULL;

	req->buf = tipc_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;
	}