1 files changed, 265 insertions, 0 deletions

diff --git a/net/tipc/user_reg.c b/net/tipc/user_reg.c
new file mode 100644
index 000000000000..106200d76587
--- /dev/null
+++ b/net/tipc/user_reg.c
@@ -0,0 +1,265 @@
+/*
+ * net/tipc/user_reg.c: TIPC user registry code
+ * 
+ * Copyright (c) 2000-2006, 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 "user_reg.h"
+
+/*
+ * TIPC user registry keeps track of users of the tipc_port interface.
+ *
+ * The registry utilizes an array of "TIPC user" entries; 
+ * a user's ID is the index of their associated array entry.
+ * Array entry 0 is not used, so userid 0 is not valid;
+ * TIPC sometimes uses this value to denote an anonymous user.
+ * The list of free entries is initially chained from last entry to entry 1.
+ */
+
+/**
+ * struct tipc_user - registered TIPC user info
+ * @next: index of next free registry entry (or -1 for an allocated entry)
+ * @callback: ptr to routine to call when TIPC mode changes (NULL if none)
+ * @usr_handle: user-defined value passed to callback routine 
+ * @ports: list of user ports owned by the user
+ */
+
+struct tipc_user {
+        int next;
+        tipc_mode_event callback;
+        void *usr_handle;
+        struct list_head ports;
+};
+
+#define MAX_USERID 64
+#define USER_LIST_SIZE ((MAX_USERID + 1) * sizeof(struct tipc_user))
+
+static struct tipc_user *users = 0;
+static u32 next_free_user = MAX_USERID + 1;
+static spinlock_t reg_lock = SPIN_LOCK_UNLOCKED;
+
+/**
+ * reg_init - create TIPC user registry (but don't activate it)
+ * 
+ * If registry has been pre-initialized it is left "as is".
+ * NOTE: This routine may be called when TIPC is inactive.
+ */
+
+static int reg_init(void)
+{
+        u32 i;
+        
+        spin_lock_bh(&reg_lock);
+        if (!users) {
+                users = (struct tipc_user *)kmalloc(USER_LIST_SIZE, GFP_ATOMIC);
+                if (users) {
+                        memset(users, 0, USER_LIST_SIZE);
+                        for (i = 1; i <= MAX_USERID; i++) {
+                                users[i].next = i - 1;
+                        }
+                        next_free_user = MAX_USERID;
+                }
+        }
+        spin_unlock_bh(&reg_lock);
+        return users ? TIPC_OK : -ENOMEM;
+}
+
+/**
+ * reg_callback - inform TIPC user about current operating mode
+ */
+
+static void reg_callback(struct tipc_user *user_ptr)
+{
+        tipc_mode_event cb;
+        void *arg;
+
+        spin_lock_bh(&reg_lock);
+        cb = user_ptr->callback;
+        arg = user_ptr->usr_handle;
+        spin_unlock_bh(&reg_lock);
+
+        if (cb)
+                cb(arg, tipc_mode, tipc_own_addr);
+}
+
+/**
+ * tipc_reg_start - activate TIPC user registry
+ */
+
+int tipc_reg_start(void)
+{
+        u32 u;
+        int res;
+
+        if ((res = reg_init()))
+                return res;
+
+        for (u = 1; u <= MAX_USERID; u++) {
+                if (users[u].callback)
+                        tipc_k_signal((Handler)reg_callback,
+                                      (unsigned long)&users[u]);
+        }
+        return TIPC_OK;
+}
+
+/**
+ * tipc_reg_stop - shut down & delete TIPC user registry
+ */
+
+void tipc_reg_stop(void)
+{               
+        int id;
+
+        if (!users)
+                return;
+
+        for (id = 1; id <= MAX_USERID; id++) {
+                if (users[id].callback)
+                        reg_callback(&users[id]);
+        }
+        kfree(users);
+        users = 0;
+}
+
+/**
+ * tipc_attach - register a TIPC user
+ *
+ * NOTE: This routine may be called when TIPC is inactive.
+ */
+
+int tipc_attach(u32 *userid, tipc_mode_event cb, void *usr_handle)
+{
+        struct tipc_user *user_ptr;
+
+        if ((tipc_mode == TIPC_NOT_RUNNING) && !cb)
+                return -ENOPROTOOPT;
+        if (!users)
+                reg_init();
+
+        spin_lock_bh(&reg_lock);
+        if (!next_free_user) {
+                spin_unlock_bh(&reg_lock);
+                return -EBUSY;
+        }
+        user_ptr = &users[next_free_user];
+        *userid = next_free_user;
+        next_free_user = user_ptr->next;
+        user_ptr->next = -1; 
+        spin_unlock_bh(&reg_lock);
+
+        user_ptr->callback = cb;
+        user_ptr->usr_handle = usr_handle;
+        INIT_LIST_HEAD(&user_ptr->ports);
+        atomic_inc(&tipc_user_count);
+        
+        if (cb && (tipc_mode != TIPC_NOT_RUNNING))
+                tipc_k_signal((Handler)reg_callback, (unsigned long)user_ptr);
+        return TIPC_OK;
+}
+
+/**
+ * tipc_detach - deregister a TIPC user
+ */
+
+void tipc_detach(u32 userid)
+{
+        struct tipc_user *user_ptr;
+        struct list_head ports_temp;
+        struct user_port *up_ptr, *temp_up_ptr;
+
+        if ((userid == 0) || (userid > MAX_USERID))
+                return;
+
+        spin_lock_bh(&reg_lock);
+        if ((!users) || (users[userid].next >= 0)) {
+                spin_unlock_bh(&reg_lock);
+                return;
+        }
+
+        user_ptr = &users[userid];
+        user_ptr->callback = NULL;              
+        INIT_LIST_HEAD(&ports_temp);
+        list_splice(&user_ptr->ports, &ports_temp);
+        user_ptr->next = next_free_user;
+        next_free_user = userid;
+        spin_unlock_bh(&reg_lock);
+
+        atomic_dec(&tipc_user_count);
+
+        list_for_each_entry_safe(up_ptr, temp_up_ptr, &ports_temp, uport_list) {
+                tipc_deleteport(up_ptr->ref);
+        }
+}
+
+/**
+ * tipc_reg_add_port - register a user's driver port
+ */
+
+int tipc_reg_add_port(struct user_port *up_ptr)
+{
+        struct tipc_user *user_ptr;
+
+        if (up_ptr->user_ref == 0)
+                return TIPC_OK;
+        if (up_ptr->user_ref > MAX_USERID)
+                return -EINVAL;
+        if ((tipc_mode == TIPC_NOT_RUNNING) || !users )
+                return -ENOPROTOOPT;
+
+        spin_lock_bh(&reg_lock);
+        user_ptr = &users[up_ptr->user_ref];
+        list_add(&up_ptr->uport_list, &user_ptr->ports);
+        spin_unlock_bh(&reg_lock);
+        return TIPC_OK;
+}
+
+/**
+ * tipc_reg_remove_port - deregister a user's driver port
+ */
+
+int tipc_reg_remove_port(struct user_port *up_ptr)
+{
+        if (up_ptr->user_ref == 0)
+                return TIPC_OK;
+        if (up_ptr->user_ref > MAX_USERID)
+                return -EINVAL;
+        if (!users )
+                return -ENOPROTOOPT;
+
+        spin_lock_bh(&reg_lock);
+        list_del_init(&up_ptr->uport_list);
+        spin_unlock_bh(&reg_lock);
+        return TIPC_OK;
+}
+