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;
+} 
+