1 files changed, 692 insertions, 0 deletions

diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
new file mode 100644
index 000000000000..3dd19fdc5a2c
--- /dev/null
+++ b/net/tipc/bearer.c
@@ -0,0 +1,692 @@
+/*
+ * net/tipc/bearer.c: TIPC bearer code
+ * 
+ * Copyright (c) 1996-2006, Ericsson AB
+ * Copyright (c) 2004-2005, 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 "config.h"
+#include "dbg.h"
+#include "bearer.h"
+#include "link.h"
+#include "port.h"
+#include "discover.h"
+#include "bcast.h"
+
+#define MAX_ADDR_STR 32
+
+static struct media *media_list = 0;
+static u32 media_count = 0;
+
+struct bearer *bearers = 0;
+
+/**
+ * media_name_valid - validate media name
+ * 
+ * Returns 1 if media name is valid, otherwise 0.
+ */
+
+static int media_name_valid(const char *name)
+{
+        u32 len;
+
+        len = strlen(name);
+        if ((len + 1) > TIPC_MAX_MEDIA_NAME)
+                return 0;
+        return (strspn(name, tipc_alphabet) == len);
+}
+
+/**
+ * media_find - locates specified media object by name
+ */
+
+static struct media *media_find(const char *name)
+{
+        struct media *m_ptr;
+        u32 i;
+
+        for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
+                if (!strcmp(m_ptr->name, name))
+                        return m_ptr;
+        }
+        return 0;
+}
+
+/**
+ * tipc_register_media - register a media type
+ * 
+ * Bearers for this media type must be activated separately at a later stage.
+ */
+
+int  tipc_register_media(u32 media_type,
+                         char *name, 
+                         int (*enable)(struct tipc_bearer *), 
+                         void (*disable)(struct tipc_bearer *), 
+                         int (*send_msg)(struct sk_buff *, 
+                                         struct tipc_bearer *,
+                                         struct tipc_media_addr *), 
+                         char *(*addr2str)(struct tipc_media_addr *a,
+                                           char *str_buf, int str_size),
+                         struct tipc_media_addr *bcast_addr,
+                         const u32 bearer_priority,
+                         const u32 link_tolerance,  /* [ms] */
+                         const u32 send_window_limit)
+{
+        struct media *m_ptr;
+        u32 media_id;
+        u32 i;
+        int res = -EINVAL;
+
+        write_lock_bh(&net_lock);
+        if (!media_list)
+                goto exit;
+
+        if (!media_name_valid(name)) {
+                warn("Media registration error: illegal name <%s>\n", name);
+                goto exit;
+        }
+        if (!bcast_addr) {
+                warn("Media registration error: no broadcast address supplied\n");
+                goto exit;
+        }
+        if (bearer_priority >= TIPC_NUM_LINK_PRI) {
+                warn("Media registration error: priority %u\n", bearer_priority);
+                goto exit;
+        }
+        if ((link_tolerance < TIPC_MIN_LINK_TOL) || 
+            (link_tolerance > TIPC_MAX_LINK_TOL)) {
+                warn("Media registration error: tolerance %u\n", link_tolerance);
+                goto exit;
+        }
+
+        media_id = media_count++;
+        if (media_id >= MAX_MEDIA) {
+                warn("Attempt to register more than %u media\n", MAX_MEDIA);
+                media_count--;
+                goto exit;
+        }
+        for (i = 0; i < media_id; i++) {
+                if (media_list[i].type_id == media_type) {
+                        warn("Attempt to register second media with type %u\n", 
+                             media_type);
+                        media_count--;
+                        goto exit;
+                }
+                if (!strcmp(name, media_list[i].name)) {
+                        warn("Attempt to re-register media name <%s>\n", name);
+                        media_count--;
+                        goto exit;
+                }
+        }
+
+        m_ptr = &media_list[media_id];
+        m_ptr->type_id = media_type;
+        m_ptr->send_msg = send_msg;
+        m_ptr->enable_bearer = enable;
+        m_ptr->disable_bearer = disable;
+        m_ptr->addr2str = addr2str;
+        memcpy(&m_ptr->bcast_addr, bcast_addr, sizeof(*bcast_addr));
+        m_ptr->bcast = 1;
+        strcpy(m_ptr->name, name);
+        m_ptr->priority = bearer_priority;
+        m_ptr->tolerance = link_tolerance;
+        m_ptr->window = send_window_limit;
+        dbg("Media <%s> registered\n", name);
+        res = 0;
+exit:
+        write_unlock_bh(&net_lock);
+        return res;
+}
+
+/**
+ * media_addr_printf - record media address in print buffer
+ */
+
+void media_addr_printf(struct print_buf *pb, struct tipc_media_addr *a)
+{
+        struct media *m_ptr;
+        u32 media_type;
+        u32 i;
+
+        media_type = ntohl(a->type);
+        for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
+                if (m_ptr->type_id == media_type)
+                        break;
+        }
+
+        if ((i < media_count) && (m_ptr->addr2str != NULL)) {
+                char addr_str[MAX_ADDR_STR];
+
+                tipc_printf(pb, "%s(%s) ", m_ptr->name, 
+                            m_ptr->addr2str(a, addr_str, sizeof(addr_str)));
+        } else {
+                unchar *addr = (unchar *)&a->dev_addr;
+
+                tipc_printf(pb, "UNKNOWN(%u):", media_type);
+                for (i = 0; i < (sizeof(*a) - sizeof(a->type)); i++) {
+                        tipc_printf(pb, "%02x ", addr[i]);
+                }
+        }
+}
+
+/**
+ * media_get_names - record names of registered media in buffer
+ */
+
+struct sk_buff *media_get_names(void)
+{
+        struct sk_buff *buf;
+        struct media *m_ptr;
+        int i;
+
+        buf = cfg_reply_alloc(MAX_MEDIA * TLV_SPACE(TIPC_MAX_MEDIA_NAME));
+        if (!buf)
+                return NULL;
+
+        read_lock_bh(&net_lock);
+        for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
+                cfg_append_tlv(buf, TIPC_TLV_MEDIA_NAME, m_ptr->name, 
+                               strlen(m_ptr->name) + 1);
+        }
+        read_unlock_bh(&net_lock);
+        return buf;
+}
+
+/**
+ * bearer_name_validate - validate & (optionally) deconstruct bearer name
+ * @name - ptr to bearer name string
+ * @name_parts - ptr to area for bearer name components (or NULL if not needed)
+ * 
+ * Returns 1 if bearer name is valid, otherwise 0.
+ */
+
+static int bearer_name_validate(const char *name, 
+                                struct bearer_name *name_parts)
+{
+        char name_copy[TIPC_MAX_BEARER_NAME];
+        char *media_name;
+        char *if_name;
+        u32 media_len;
+        u32 if_len;
+
+        /* copy bearer name & ensure length is OK */
+
+        name_copy[TIPC_MAX_BEARER_NAME - 1] = 0;
+        /* need above in case non-Posix strncpy() doesn't pad with nulls */
+        strncpy(name_copy, name, TIPC_MAX_BEARER_NAME);
+        if (name_copy[TIPC_MAX_BEARER_NAME - 1] != 0)
+                return 0;
+
+        /* ensure all component parts of bearer name are present */
+
+        media_name = name_copy;
+        if ((if_name = strchr(media_name, ':')) == NULL)
+                return 0;
+        *(if_name++) = 0;
+        media_len = if_name - media_name;
+        if_len = strlen(if_name) + 1;
+
+        /* validate component parts of bearer name */
+
+        if ((media_len <= 1) || (media_len > TIPC_MAX_MEDIA_NAME) || 
+            (if_len <= 1) || (if_len > TIPC_MAX_IF_NAME) || 
+            (strspn(media_name, tipc_alphabet) != (media_len - 1)) ||
+            (strspn(if_name, tipc_alphabet) != (if_len - 1)))
+                return 0;
+
+        /* return bearer name components, if necessary */
+
+        if (name_parts) {
+                strcpy(name_parts->media_name, media_name);
+                strcpy(name_parts->if_name, if_name);
+        }
+        return 1;
+}
+
+/**
+ * bearer_find - locates bearer object with matching bearer name
+ */
+
+static struct bearer *bearer_find(const char *name)
+{
+        struct bearer *b_ptr;
+        u32 i;
+
+        for (i = 0, b_ptr = bearers; i < MAX_BEARERS; i++, b_ptr++) {
+                if (b_ptr->active && (!strcmp(b_ptr->publ.name, name)))
+                        return b_ptr;
+        }
+        return 0;
+}
+
+/**
+ * bearer_find - locates bearer object with matching interface name
+ */
+
+struct bearer *bearer_find_interface(const char *if_name)
+{
+        struct bearer *b_ptr;
+        char *b_if_name;
+        u32 i;
+
+        for (i = 0, b_ptr = bearers; i < MAX_BEARERS; i++, b_ptr++) {
+                if (!b_ptr->active)
+                        continue;
+                b_if_name = strchr(b_ptr->publ.name, ':') + 1;
+                if (!strcmp(b_if_name, if_name))
+                        return b_ptr;
+        }
+        return 0;
+}
+
+/**
+ * bearer_get_names - record names of bearers in buffer
+ */
+
+struct sk_buff *bearer_get_names(void)
+{
+        struct sk_buff *buf;
+        struct media *m_ptr;
+        struct bearer *b_ptr;
+        int i, j;
+
+        buf = cfg_reply_alloc(MAX_BEARERS * TLV_SPACE(TIPC_MAX_BEARER_NAME));
+        if (!buf)
+                return NULL;
+
+        read_lock_bh(&net_lock);
+        for (i = 0, m_ptr = media_list; i < media_count; i++, m_ptr++) {
+                for (j = 0; j < MAX_BEARERS; j++) {
+                        b_ptr = &bearers[j];
+                        if (b_ptr->active && (b_ptr->media == m_ptr)) {
+                                cfg_append_tlv(buf, TIPC_TLV_BEARER_NAME, 
+                                               b_ptr->publ.name, 
+                                               strlen(b_ptr->publ.name) + 1);
+                        }
+                }
+        }
+        read_unlock_bh(&net_lock);
+        return buf;
+}
+
+void bearer_add_dest(struct bearer *b_ptr, u32 dest)
+{
+        nmap_add(&b_ptr->nodes, dest);
+        disc_update_link_req(b_ptr->link_req);
+        bcbearer_sort();
+}
+
+void bearer_remove_dest(struct bearer *b_ptr, u32 dest)
+{
+        nmap_remove(&b_ptr->nodes, dest);
+        disc_update_link_req(b_ptr->link_req);
+        bcbearer_sort();
+}
+
+/*
+ * bearer_push(): Resolve bearer congestion. Force the waiting
+ * links to push out their unsent packets, one packet per link
+ * per iteration, until all packets are gone or congestion reoccurs.
+ * 'net_lock' is read_locked when this function is called
+ * bearer.lock must be taken before calling
+ * Returns binary true(1) ore false(0)
+ */
+static int bearer_push(struct bearer *b_ptr)
+{
+        u32 res = TIPC_OK;
+        struct link *ln, *tln;
+
+        if (b_ptr->publ.blocked)
+                return 0;
+
+        while (!list_empty(&b_ptr->cong_links) && (res != PUSH_FAILED)) {
+                list_for_each_entry_safe(ln, tln, &b_ptr->cong_links, link_list) {
+                        res = link_push_packet(ln);
+                        if (res == PUSH_FAILED)
+                                break;
+                        if (res == PUSH_FINISHED)
+                                list_move_tail(&ln->link_list, &b_ptr->links);
+                }
+        }
+        return list_empty(&b_ptr->cong_links);
+}
+
+void bearer_lock_push(struct bearer *b_ptr)
+{
+        int res;
+
+        spin_lock_bh(&b_ptr->publ.lock);
+        res = bearer_push(b_ptr);
+        spin_unlock_bh(&b_ptr->publ.lock);
+        if (res)
+                bcbearer_push();
+}
+
+
+/*
+ * Interrupt enabling new requests after bearer congestion or blocking:    
+ * See bearer_send().   
+ */
+void tipc_continue(struct tipc_bearer *tb_ptr)
+{
+        struct bearer *b_ptr = (struct bearer *)tb_ptr;
+
+        spin_lock_bh(&b_ptr->publ.lock);
+        b_ptr->continue_count++;
+        if (!list_empty(&b_ptr->cong_links))
+                k_signal((Handler)bearer_lock_push, (unsigned long)b_ptr);
+        b_ptr->publ.blocked = 0;
+        spin_unlock_bh(&b_ptr->publ.lock);
+}
+
+/*
+ * Schedule link for sending of messages after the bearer 
+ * has been deblocked by 'continue()'. This method is called 
+ * when somebody tries to send a message via this link while 
+ * the bearer is congested. 'net_lock' is in read_lock here
+ * bearer.lock is busy
+ */
+
+static void bearer_schedule_unlocked(struct bearer *b_ptr, struct link *l_ptr)
+{
+        list_move_tail(&l_ptr->link_list, &b_ptr->cong_links);
+}
+
+/*
+ * Schedule link for sending of messages after the bearer 
+ * has been deblocked by 'continue()'. This method is called 
+ * when somebody tries to send a message via this link while 
+ * the bearer is congested. 'net_lock' is in read_lock here,
+ * bearer.lock is free
+ */
+
+void bearer_schedule(struct bearer *b_ptr, struct link *l_ptr)
+{
+        spin_lock_bh(&b_ptr->publ.lock);
+        bearer_schedule_unlocked(b_ptr, l_ptr);
+        spin_unlock_bh(&b_ptr->publ.lock);
+}
+
+
+/*
+ * bearer_resolve_congestion(): Check if there is bearer congestion,
+ * and if there is, try to resolve it before returning.
+ * 'net_lock' is read_locked when this function is called
+ */
+int bearer_resolve_congestion(struct bearer *b_ptr, struct link *l_ptr)
+{
+        int res = 1;
+
+        if (list_empty(&b_ptr->cong_links))
+                return 1;
+        spin_lock_bh(&b_ptr->publ.lock);
+        if (!bearer_push(b_ptr)) {
+                bearer_schedule_unlocked(b_ptr, l_ptr);
+                res = 0;
+        }
+        spin_unlock_bh(&b_ptr->publ.lock);
+        return res;
+}
+
+
+/**
+ * tipc_enable_bearer - enable bearer with the given name
+ */              
+
+int tipc_enable_bearer(const char *name, u32 bcast_scope, u32 priority)
+{
+        struct bearer *b_ptr;
+        struct media *m_ptr;
+        struct bearer_name b_name;
+        char addr_string[16];
+        u32 bearer_id;
+        u32 with_this_prio;
+        u32 i;
+        int res = -EINVAL;
+
+        if (tipc_mode != TIPC_NET_MODE)
+                return -ENOPROTOOPT;
+        if (!bearer_name_validate(name, &b_name) ||
+            !addr_domain_valid(bcast_scope) ||
+            !in_scope(bcast_scope, tipc_own_addr) ||
+            (priority > TIPC_NUM_LINK_PRI))
+                return -EINVAL;
+
+        write_lock_bh(&net_lock);
+        if (!bearers)
+                goto failed;
+
+        m_ptr = media_find(b_name.media_name);
+        if (!m_ptr) {
+                warn("No media <%s>\n", b_name.media_name);
+                goto failed;
+        }
+        if (priority == TIPC_NUM_LINK_PRI)
+                priority = m_ptr->priority;
+
+restart:
+        bearer_id = MAX_BEARERS;
+        with_this_prio = 1;
+        for (i = MAX_BEARERS; i-- != 0; ) {
+                if (!bearers[i].active) {
+                        bearer_id = i;
+                        continue;
+                }
+                if (!strcmp(name, bearers[i].publ.name)) {
+                        warn("Bearer <%s> already enabled\n", name);
+                        goto failed;
+                }
+                if ((bearers[i].priority == priority) &&
+                    (++with_this_prio > 2)) {
+                        if (priority-- == 0) {
+                                warn("Third bearer <%s> with priority %u, unable to lower to %u\n",
+                                     name, priority + 1, priority);
+                                goto failed;
+                        }
+                        warn("Third bearer <%s> with priority %u, lowering to %u\n",
+                             name, priority + 1, priority);
+                        goto restart;
+                }
+        }
+        if (bearer_id >= MAX_BEARERS) {
+                warn("Attempt to enable more than %d bearers\n", MAX_BEARERS);
+                goto failed;
+        }
+
+        b_ptr = &bearers[bearer_id];
+        memset(b_ptr, 0, sizeof(struct bearer));
+
+        strcpy(b_ptr->publ.name, name);
+        res = m_ptr->enable_bearer(&b_ptr->publ);
+        if (res) {
+                warn("Failed to enable bearer <%s>\n", name);
+                goto failed;
+        }
+
+        b_ptr->identity = bearer_id;
+        b_ptr->media = m_ptr;
+        b_ptr->net_plane = bearer_id + 'A';
+        b_ptr->active = 1;
+        b_ptr->detect_scope = bcast_scope;
+        b_ptr->priority = priority;
+        INIT_LIST_HEAD(&b_ptr->cong_links);
+        INIT_LIST_HEAD(&b_ptr->links);
+        if (m_ptr->bcast) {
+                b_ptr->link_req = disc_init_link_req(b_ptr, &m_ptr->bcast_addr,
+                                                     bcast_scope, 2);
+        }
+        b_ptr->publ.lock = SPIN_LOCK_UNLOCKED;
+        write_unlock_bh(&net_lock);
+        info("Enabled bearer <%s>, discovery domain %s\n",
+             name, addr_string_fill(addr_string, bcast_scope));
+        return 0;
+failed:
+        write_unlock_bh(&net_lock);
+        return res;
+}
+
+/**
+ * tipc_block_bearer(): Block the bearer with the given name,
+ *                      and reset all its links
+ */
+
+int tipc_block_bearer(const char *name)
+{
+        struct bearer *b_ptr = 0;
+        struct link *l_ptr;
+        struct link *temp_l_ptr;
+
+        if (tipc_mode != TIPC_NET_MODE)
+                return -ENOPROTOOPT;
+
+        read_lock_bh(&net_lock);
+        b_ptr = bearer_find(name);
+        if (!b_ptr) {
+                warn("Attempt to block unknown bearer <%s>\n", name);
+                read_unlock_bh(&net_lock);
+                return -EINVAL;
+        }
+
+        spin_lock_bh(&b_ptr->publ.lock);
+        b_ptr->publ.blocked = 1;
+        list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
+                struct node *n_ptr = l_ptr->owner;
+
+                spin_lock_bh(&n_ptr->lock);
+                link_reset(l_ptr);
+                spin_unlock_bh(&n_ptr->lock);
+        }
+        spin_unlock_bh(&b_ptr->publ.lock);
+        read_unlock_bh(&net_lock);
+        info("Blocked bearer <%s>\n", name);
+        return TIPC_OK;
+}
+
+/**
+ * bearer_disable -
+ * 
+ * Note: This routine assumes caller holds net_lock.
+ */
+
+static int bearer_disable(const char *name)
+{
+        struct bearer *b_ptr;
+        struct link *l_ptr;
+        struct link *temp_l_ptr;
+
+        if (tipc_mode != TIPC_NET_MODE)
+                return -ENOPROTOOPT;
+
+        b_ptr = bearer_find(name);
+        if (!b_ptr) {
+                warn("Attempt to disable unknown bearer <%s>\n", name);
+                return -EINVAL;
+        }
+
+        disc_stop_link_req(b_ptr->link_req);
+        spin_lock_bh(&b_ptr->publ.lock);
+        b_ptr->link_req = NULL;
+        b_ptr->publ.blocked = 1;
+        if (b_ptr->media->disable_bearer) {
+                spin_unlock_bh(&b_ptr->publ.lock);
+                write_unlock_bh(&net_lock);
+                b_ptr->media->disable_bearer(&b_ptr->publ);
+                write_lock_bh(&net_lock);
+                spin_lock_bh(&b_ptr->publ.lock);
+        }
+        list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
+                link_delete(l_ptr);
+        }
+        spin_unlock_bh(&b_ptr->publ.lock);
+        info("Disabled bearer <%s>\n", name);
+        memset(b_ptr, 0, sizeof(struct bearer));
+        return TIPC_OK;
+}
+
+int tipc_disable_bearer(const char *name)
+{
+        int res;
+
+        write_lock_bh(&net_lock);
+        res = bearer_disable(name);
+        write_unlock_bh(&net_lock);
+        return res;
+}
+
+
+
+int bearer_init(void)
+{
+        int res;
+
+        write_lock_bh(&net_lock);
+        bearers = kmalloc(MAX_BEARERS * sizeof(struct bearer), GFP_ATOMIC);
+        media_list = kmalloc(MAX_MEDIA * sizeof(struct media), GFP_ATOMIC);
+        if (bearers && media_list) {
+                memset(bearers, 0, MAX_BEARERS * sizeof(struct bearer));
+                memset(media_list, 0, MAX_MEDIA * sizeof(struct media));
+                res = TIPC_OK;
+        } else {
+                kfree(bearers);
+                kfree(media_list);
+                bearers = 0;
+                media_list = 0;
+                res = -ENOMEM;
+        }
+        write_unlock_bh(&net_lock);
+        return res;
+}
+
+void bearer_stop(void)
+{
+        u32 i;
+
+        if (!bearers)
+                return;
+
+        for (i = 0; i < MAX_BEARERS; i++) {
+                if (bearers[i].active)
+                        bearers[i].publ.blocked = 1;
+        }
+        for (i = 0; i < MAX_BEARERS; i++) {
+                if (bearers[i].active)
+                        bearer_disable(bearers[i].publ.name);
+        }
+        kfree(bearers);
+        kfree(media_list);
+        bearers = 0;
+        media_list = 0;
+        media_count = 0;
+}
+
+