Staging: batman-adv: atomic variable for vis-srv activation

This fixes the bug discovered by Marek Lindner which did not allow
turning on the vis-server before an interface has been added. With this
patch we are using a global atomic variable for activating and
deactiating the vis-server-mode, which can be used before
inserting an interface.

Signed-off-by: Linus Luessing <linus.luessing@web.de>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

6 files changed, 18 insertions, 51 deletions

diff --git a/drivers/staging/batman-adv/main.c b/drivers/staging/batman-adv/main.c
index 3f780753a2bf..2e0b482e710a 100644
--- a/drivers/staging/batman-adv/main.c
+++ b/drivers/staging/batman-adv/main.c
@@ -43,6 +43,7 @@ DEFINE_SPINLOCK(forw_bcast_list_lock);
 
 atomic_t originator_interval;
 atomic_t vis_interval;
+atomic_t vis_mode;
 atomic_t aggregation_enabled;
 int16_t num_hna;
 int16_t num_ifs;
@@ -83,6 +84,7 @@ int init_module(void)
         atomic_set(&originator_interval, 1000);
         atomic_set(&vis_interval, 1000);/* TODO: raise this later, this is only
                                          * for debugging now. */
+        atomic_set(&vis_mode, VIS_TYPE_CLIENT_UPDATE);
         atomic_set(&aggregation_enabled, 1);
 
         /* the name should not be longer than 10 chars - see
diff --git a/drivers/staging/batman-adv/main.h b/drivers/staging/batman-adv/main.h
index eb6a702c6444..deb41f5beda6 100644
--- a/drivers/staging/batman-adv/main.h
+++ b/drivers/staging/batman-adv/main.h
@@ -130,6 +130,7 @@ extern spinlock_t forw_bcast_list_lock;
 
 extern atomic_t originator_interval;
 extern atomic_t vis_interval;
+extern atomic_t vis_mode;
 extern atomic_t aggregation_enabled;
 extern int16_t num_hna;
 extern int16_t num_ifs;
diff --git a/drivers/staging/batman-adv/proc.c b/drivers/staging/batman-adv/proc.c
index 68c36b097a07..0eadc6b48d75 100644
--- a/drivers/staging/batman-adv/proc.c
+++ b/drivers/staging/batman-adv/proc.c
@@ -338,11 +338,11 @@ static ssize_t proc_vis_srv_write(struct file *file, const char __user * buffer,
         if ((strcmp(vis_mode_string, "client") == 0) ||
                         (strcmp(vis_mode_string, "disabled") == 0)) {
                 printk(KERN_INFO "batman-adv:Setting VIS mode to client (disabling vis server)\n");
-                vis_set_mode(VIS_TYPE_CLIENT_UPDATE);
+                atomic_set(&vis_mode, VIS_TYPE_CLIENT_UPDATE);
         } else if ((strcmp(vis_mode_string, "server") == 0) ||
                         (strcmp(vis_mode_string, "enabled") == 0)) {
                 printk(KERN_INFO "batman-adv:Setting VIS mode to server (enabling vis server)\n");
-                vis_set_mode(VIS_TYPE_SERVER_SYNC);
+                atomic_set(&vis_mode, VIS_TYPE_SERVER_SYNC);
         } else
                 printk(KERN_ERR "batman-adv:Unknown VIS mode: %s\n",
                        vis_mode_string);
@@ -353,12 +353,12 @@ static ssize_t proc_vis_srv_write(struct file *file, const char __user * buffer,
 
 static int proc_vis_srv_read(struct seq_file *seq, void *offset)
 {
-        int vis_server = is_vis_server();
+        int vis_server = atomic_read(&vis_mode);
 
         seq_printf(seq, "[%c] client mode (server disabled) \n",
-                        (!vis_server) ? 'x' : ' ');
+                        (vis_server == VIS_TYPE_CLIENT_UPDATE) ? 'x' : ' ');
         seq_printf(seq, "[%c] server mode (server enabled) \n",
-                        (vis_server) ? 'x' : ' ');
+                        (vis_server == VIS_TYPE_SERVER_SYNC) ? 'x' : ' ');
 
         return 0;
 }
@@ -377,9 +377,10 @@ static int proc_vis_data_read(struct seq_file *seq, void *offset)
         int i;
         char tmp_addr_str[ETH_STR_LEN];
         unsigned long flags;
+        int vis_server = atomic_read(&vis_mode);
 
         rcu_read_lock();
-        if (list_empty(&if_list) || (!is_vis_server())) {
+        if (list_empty(&if_list) || (vis_server == VIS_TYPE_CLIENT_UPDATE)) {
                 rcu_read_unlock();
                 goto end;
         }
@@ -672,5 +673,3 @@ int setup_procfs(void)
 
         return 0;
 }
-
-
diff --git a/drivers/staging/batman-adv/send.c b/drivers/staging/batman-adv/send.c
index 944b2cdbdff8..2a9fac8c240e 100644
--- a/drivers/staging/batman-adv/send.c
+++ b/drivers/staging/batman-adv/send.c
@@ -248,6 +248,7 @@ void schedule_own_packet(struct batman_if *batman_if)
 {
         unsigned long send_time;
         struct batman_packet *batman_packet;
+        int vis_server = atomic_read(&vis_mode);
 
         /**
          * the interface gets activated here to avoid race conditions between
@@ -272,7 +273,7 @@ void schedule_own_packet(struct batman_if *batman_if)
         /* change sequence number to network order */
         batman_packet->seqno = htons((uint16_t)atomic_read(&batman_if->seqno));
 
-        if (is_vis_server())
+        if (vis_server == VIS_TYPE_SERVER_SYNC)
                 batman_packet->flags = VIS_SERVER;
         else
                 batman_packet->flags = 0;
diff --git a/drivers/staging/batman-adv/vis.c b/drivers/staging/batman-adv/vis.c
index ec8bb3f382c6..fedec1bb3097 100644
--- a/drivers/staging/batman-adv/vis.c
+++ b/drivers/staging/batman-adv/vis.c
@@ -48,41 +48,6 @@ static void free_info(void *data)
         kfree(info);
 }
 
-/* set the mode of the visualization to client or server */
-void vis_set_mode(int mode)
-{
-        unsigned long flags;
-        spin_lock_irqsave(&vis_hash_lock, flags);
-
-        if (my_vis_info != NULL)
-                my_vis_info->packet.vis_type = mode;
-
-        spin_unlock_irqrestore(&vis_hash_lock, flags);
-}
-
-/* is_vis_server(), locked outside */
-static int is_vis_server_locked(void)
-{
-        if (my_vis_info != NULL)
-                if (my_vis_info->packet.vis_type == VIS_TYPE_SERVER_SYNC)
-                        return 1;
-
-        return 0;
-}
-
-/* get the current set mode */
-int is_vis_server(void)
-{
-        int ret = 0;
-        unsigned long flags;
-
-        spin_lock_irqsave(&vis_hash_lock, flags);
-        ret = is_vis_server_locked();
-        spin_unlock_irqrestore(&vis_hash_lock, flags);
-
-        return ret;
-}
-
 /* Compare two vis packets, used by the hashing algorithm */
 static int vis_info_cmp(void *data1, void *data2)
 {
@@ -271,6 +236,7 @@ void receive_server_sync_packet(struct vis_packet *vis_packet, int vis_info_len)
         struct vis_info *info;
         int is_new;
         unsigned long flags;
+        int vis_server = atomic_read(&vis_mode);
 
         spin_lock_irqsave(&vis_hash_lock, flags);
         info = add_packet(vis_packet, vis_info_len, &is_new);
@@ -279,7 +245,7 @@ void receive_server_sync_packet(struct vis_packet *vis_packet, int vis_info_len)
 
         /* only if we are server ourselves and packet is newer than the one in
          * hash.*/
-        if (is_vis_server_locked() && is_new) {
+        if (vis_server == VIS_TYPE_SERVER_SYNC && is_new) {
                 memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN);
                 if (list_empty(&info->send_list))
                         list_add_tail(&info->send_list, &send_list);
@@ -295,6 +261,7 @@ void receive_client_update_packet(struct vis_packet *vis_packet,
         struct vis_info *info;
         int is_new;
         unsigned long flags;
+        int vis_server = atomic_read(&vis_mode);
 
         /* clients shall not broadcast. */
         if (is_bcast(vis_packet->target_orig))
@@ -308,7 +275,7 @@ void receive_client_update_packet(struct vis_packet *vis_packet,
 
 
         /* send only if we're the target server or ... */
-        if (is_vis_server_locked() &&
+        if (vis_server == VIS_TYPE_SERVER_SYNC  &&
             is_my_mac(info->packet.target_orig) &&
             is_new) {
                 info->packet.vis_type = VIS_TYPE_SERVER_SYNC;   /* upgrade! */
@@ -372,6 +339,7 @@ static int generate_vis_packet(void)
         unsigned long flags;
 
         info->first_seen = jiffies;
+        info->packet.vis_type = atomic_read(&vis_mode);
 
         spin_lock_irqsave(&orig_hash_lock, flags);
         memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN);
@@ -379,7 +347,7 @@ static int generate_vis_packet(void)
         info->packet.seqno++;
         info->packet.entries = 0;
 
-        if (!is_vis_server_locked()) {
+        if (info->packet.vis_type == VIS_TYPE_CLIENT_UPDATE) {
                 best_tq = find_best_vis_server(info);
                 if (best_tq < 0) {
                         spin_unlock_irqrestore(&orig_hash_lock, flags);
@@ -577,7 +545,6 @@ int vis_init(void)
         INIT_LIST_HEAD(&my_vis_info->send_list);
         my_vis_info->packet.version = COMPAT_VERSION;
         my_vis_info->packet.packet_type = BAT_VIS;
-        my_vis_info->packet.vis_type = VIS_TYPE_CLIENT_UPDATE;
         my_vis_info->packet.ttl = TTL;
         my_vis_info->packet.seqno = 0;
         my_vis_info->packet.entries = 0;
@@ -628,4 +595,3 @@ static void start_vis_timer(void)
         queue_delayed_work(bat_event_workqueue, &vis_timer_wq,
                            (atomic_read(&vis_interval) * HZ) / 1000);
 }
-
diff --git a/drivers/staging/batman-adv/vis.h b/drivers/staging/batman-adv/vis.h
index 2e24258e69a4..0cdafde0ec3a 100644
--- a/drivers/staging/batman-adv/vis.h
+++ b/drivers/staging/batman-adv/vis.h
@@ -48,8 +48,6 @@ struct recvlist_node {
 extern struct hashtable_t *vis_hash;
 extern spinlock_t vis_hash_lock;
 
-void vis_set_mode(int mode);
-int is_vis_server(void);
 void proc_vis_read_entry(struct seq_file *seq,
                                 struct vis_info_entry *entry,
                                 struct hlist_head *if_list,