Staging: batman-adv: add routing debug log accessible via debugfs

All routing debug messages are saved in a ring buffer that can be
read via the debugfs file "log".
Note that CONFIG_BATMAN_ADV_DEBUG must be activated to have the
debug logs compiled in.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/batman-adv/aggregation.c

@@ -106,11 +106,14 @@ static void new_aggregated_packet(unsigned char *packet_buff,
 {
 	struct forw_packet *forw_packet_aggr;
 	unsigned long flags;
+	/* FIXME: each batman_if will be attached to a softif */
+	struct bat_priv *bat_priv = netdev_priv(soft_device);
 
 	/* own packet should always be scheduled */
 	if (!own_packet) {
 		if (!atomic_dec_not_zero(&batman_queue_left)) {
-			bat_dbg(DBG_BATMAN, "batman packet queue full\n");
+			bat_dbg(DBG_BATMAN, bat_priv,
+				"batman packet queue full\n");
 			return;
 		}
 	}

drivers/staging/batman-adv/bat_debugfs.c

@@ -31,6 +31,193 @@
 
 static struct dentry *bat_debugfs;
 
+#ifdef CONFIG_BATMAN_ADV_DEBUG
+#define LOG_BUFF_MASK (log_buff_len-1)
+#define LOG_BUFF(idx) (debug_log->log_buff[(idx) & LOG_BUFF_MASK])
+
+static int log_buff_len = LOG_BUF_LEN;
+
+static void emit_log_char(struct debug_log *debug_log, char c)
+{
+	LOG_BUFF(debug_log->log_end) = c;
+	debug_log->log_end++;
+
+	if (debug_log->log_end - debug_log->log_start > log_buff_len)
+		debug_log->log_start = debug_log->log_end - log_buff_len;
+}
+
+static int fdebug_log(struct debug_log *debug_log, char *fmt, ...)
+{
+	int printed_len;
+	va_list args;
+	static char debug_log_buf[256];
+	char *p;
+	unsigned long flags;
+
+	if (!debug_log)
+		return 0;
+
+	spin_lock_irqsave(&debug_log->lock, flags);
+	va_start(args, fmt);
+	printed_len = vscnprintf(debug_log_buf, sizeof(debug_log_buf),
+				 fmt, args);
+	va_end(args);
+
+	for (p = debug_log_buf; *p != 0; p++)
+		emit_log_char(debug_log, *p);
+
+	spin_unlock_irqrestore(&debug_log->lock, flags);
+
+	wake_up(&debug_log->queue_wait);
+
+	return 0;
+}
+
+int debug_log(struct bat_priv *bat_priv, char *fmt, ...)
+{
+	va_list args;
+	char tmp_log_buf[256];
+
+	va_start(args, fmt);
+	vscnprintf(tmp_log_buf, sizeof(tmp_log_buf), fmt, args);
+	fdebug_log(bat_priv->debug_log, "[%10u] %s",
+		   (jiffies / HZ), tmp_log_buf);
+	va_end(args);
+
+	return 0;
+}
+
+static int log_open(struct inode *inode, struct file *file)
+{
+	file->private_data = inode->i_private;
+	inc_module_count();
+	return 0;
+}
+
+static int log_release(struct inode *inode, struct file *file)
+{
+	dec_module_count();
+	return 0;
+}
+
+static ssize_t log_read(struct file *file, char __user *buf,
+			size_t count, loff_t *ppos)
+{
+	struct bat_priv *bat_priv = (struct bat_priv *)file->private_data;
+	struct debug_log *debug_log = bat_priv->debug_log;
+	int error, i = 0;
+	char c;
+	unsigned long flags;
+
+	if ((file->f_flags & O_NONBLOCK) &&
+	    !(debug_log->log_end - debug_log->log_start))
+		return -EAGAIN;
+
+	if ((!buf) || (count < 0))
+		return -EINVAL;
+
+	if (count == 0)
+		return 0;
+
+	if (!access_ok(VERIFY_WRITE, buf, count))
+		return -EFAULT;
+
+	error = wait_event_interruptible(debug_log->queue_wait,
+				(debug_log->log_start - debug_log->log_end));
+
+	if (error)
+		return error;
+
+	spin_lock_irqsave(&debug_log->lock, flags);
+
+	while ((!error) && (i < count) &&
+	       (debug_log->log_start != debug_log->log_end)) {
+		c = LOG_BUFF(debug_log->log_start);
+
+		debug_log->log_start++;
+
+		spin_unlock_irqrestore(&debug_log->lock, flags);
+
+		error = __put_user(c, buf);
+
+		spin_lock_irqsave(&debug_log->lock, flags);
+
+		buf++;
+		i++;
+
+	}
+
+	spin_unlock_irqrestore(&debug_log->lock, flags);
+
+	if (!error)
+		return i;
+
+	return error;
+}
+
+static unsigned int log_poll(struct file *file, poll_table *wait)
+{
+	struct bat_priv *bat_priv = (struct bat_priv *)file->private_data;
+	struct debug_log *debug_log = bat_priv->debug_log;
+
+	poll_wait(file, &debug_log->queue_wait, wait);
+
+	if (debug_log->log_end - debug_log->log_start)
+		return POLLIN | POLLRDNORM;
+
+	return 0;
+}
+
+static const struct file_operations log_fops = {
+	.open           = log_open,
+	.release        = log_release,
+	.read           = log_read,
+	.poll           = log_poll,
+};
+
+static int debug_log_setup(struct bat_priv *bat_priv)
+{
+	struct dentry *d;
+
+	if (!bat_priv->debug_dir)
+		goto err;
+
+	bat_priv->debug_log = kzalloc(sizeof(struct debug_log), GFP_ATOMIC);
+	if (!bat_priv->debug_log)
+		goto err;
+
+	spin_lock_init(&bat_priv->debug_log->lock);
+	init_waitqueue_head(&bat_priv->debug_log->queue_wait);
+
+	d = debugfs_create_file("log", S_IFREG | S_IRUSR,
+				bat_priv->debug_dir, bat_priv, &log_fops);
+	if (d)
+		goto err;
+
+	return 0;
+
+err:
+	return 1;
+}
+
+static void debug_log_cleanup(struct bat_priv *bat_priv)
+{
+	kfree(bat_priv->debug_log);
+	bat_priv->debug_log = NULL;
+}
+#else /* CONFIG_BATMAN_ADV_DEBUG */
+static int debug_log_setup(struct bat_priv *bat_priv)
+{
+	bat_priv->debug_log = NULL;
+	return 0;
+}
+
+static void debug_log_cleanup(struct bat_priv *bat_priv)
+{
+	return;
+}
+#endif
+
 static int originators_open(struct inode *inode, struct file *file)
 {
 	struct net_device *net_dev = (struct net_device *)inode->i_private;
@@ -114,6 +301,7 @@ int debugfs_add_meshif(struct net_device *dev)
 		goto out;
 
 	bat_socket_setup(bat_priv);
+	debug_log_setup(bat_priv);
 
 	for (bat_debug = mesh_debuginfos; *bat_debug; ++bat_debug) {
 		file = debugfs_create_file(((*bat_debug)->attr).name,
@@ -143,6 +331,8 @@ void debugfs_del_meshif(struct net_device *dev)
 {
 	struct bat_priv *bat_priv = netdev_priv(dev);
 
+	debug_log_cleanup(bat_priv);
+
 	if (bat_debugfs) {
 		debugfs_remove_recursive(bat_priv->debug_dir);
 		bat_priv->debug_dir = NULL;

drivers/staging/batman-adv/bat_sysfs.c

@@ -229,18 +229,70 @@ static ssize_t store_orig_interval(struct kobject *kobj, struct attribute *attr,
 	return count;
 }
 
+#ifdef CONFIG_BATMAN_ADV_DEBUG
+static ssize_t show_log_level(struct kobject *kobj, struct attribute *attr,
+			     char *buff)
+{
+	struct device *dev = to_dev(kobj->parent);
+	struct bat_priv *bat_priv = netdev_priv(to_net_dev(dev));
+	int log_level = atomic_read(&bat_priv->log_level);
+
+	return sprintf(buff, "%d\n", log_level);
+}
+
+static ssize_t store_log_level(struct kobject *kobj, struct attribute *attr,
+			      char *buff, size_t count)
+{
+	struct device *dev = to_dev(kobj->parent);
+	struct net_device *net_dev = to_net_dev(dev);
+	struct bat_priv *bat_priv = netdev_priv(net_dev);
+	unsigned long log_level_tmp;
+	int ret;
+
+	ret = strict_strtoul(buff, 10, &log_level_tmp);
+	if (ret) {
+		printk(KERN_INFO "batman-adv:Invalid parameter for 'log_level' setting on mesh %s received: %s\n",
+		       net_dev->name, buff);
+		return -EINVAL;
+	}
+
+	if (log_level_tmp > 3) {
+		printk(KERN_INFO "batman-adv:New log level too big: %li (max: %i)\n",
+		       log_level_tmp, 3);
+		return -EINVAL;
+	}
+
+	if (atomic_read(&bat_priv->log_level) == log_level_tmp)
+		return count;
+
+	printk(KERN_INFO
+	       "batman-adv:Changing log level from: %i to: %li on mesh: %s\n",
+	       atomic_read(&bat_priv->log_level),
+	       log_level_tmp, net_dev->name);
+
+	atomic_set(&bat_priv->log_level, (unsigned)log_level_tmp);
+	return count;
+}
+#endif
+
 static BAT_ATTR(aggregated_ogms, S_IRUGO | S_IWUSR,
 		show_aggr_ogms, store_aggr_ogms);
 static BAT_ATTR(bonding, S_IRUGO | S_IWUSR, show_bond, store_bond);
 static BAT_ATTR(vis_mode, S_IRUGO | S_IWUSR, show_vis_mode, store_vis_mode);
 static BAT_ATTR(orig_interval, S_IRUGO | S_IWUSR,
 		show_orig_interval, store_orig_interval);
+#ifdef CONFIG_BATMAN_ADV_DEBUG
+static BAT_ATTR(log_level, S_IRUGO | S_IWUSR, show_log_level, store_log_level);
+#endif
 
 static struct bat_attribute *mesh_attrs[] = {
 	&bat_attr_aggregated_ogms,
 	&bat_attr_bonding,
 	&bat_attr_vis_mode,
 	&bat_attr_orig_interval,
+#ifdef CONFIG_BATMAN_ADV_DEBUG
+	&bat_attr_log_level,
+#endif
 	NULL,
 };
 
@@ -257,6 +309,8 @@ int sysfs_add_meshif(struct net_device *dev)
 	atomic_set(&bat_priv->bonding_enabled, 0);
 	atomic_set(&bat_priv->vis_mode, VIS_TYPE_CLIENT_UPDATE);
 	atomic_set(&bat_priv->orig_interval, 1000);
+	atomic_set(&bat_priv->log_level, 0);
+
 	bat_priv->primary_if = NULL;
 	bat_priv->num_ifaces = 0;
 

drivers/staging/batman-adv/bitarray.c

@@ -128,6 +128,9 @@ static void bit_reset_window(TYPE_OF_WORD *seq_bits)
 char bit_get_packet(TYPE_OF_WORD *seq_bits, int32_t seq_num_diff,
 		    int8_t set_mark)
 {
+	/* FIXME: each orig_node->batman_if will be attached to a softif */
+	struct bat_priv *bat_priv = netdev_priv(soft_device);
+
 	/* sequence number is slightly older. We already got a sequence number
 	 * higher than this one, so we just mark it. */
 
@@ -152,7 +155,7 @@ char bit_get_packet(TYPE_OF_WORD *seq_bits, int32_t seq_num_diff,
 
 	if ((seq_num_diff >= TQ_LOCAL_WINDOW_SIZE)
 		|| (seq_num_diff < EXPECTED_SEQNO_RANGE)) {
-		bat_dbg(DBG_BATMAN,
+		bat_dbg(DBG_BATMAN, bat_priv,
 			"We missed a lot of packets (%i) !\n",
 			seq_num_diff - 1);
 		bit_reset_window(seq_bits);
@@ -169,7 +172,7 @@ char bit_get_packet(TYPE_OF_WORD *seq_bits, int32_t seq_num_diff,
 	if ((seq_num_diff <= -TQ_LOCAL_WINDOW_SIZE)
 		|| (seq_num_diff >= EXPECTED_SEQNO_RANGE)) {
 
-		bat_dbg(DBG_BATMAN,
+		bat_dbg(DBG_BATMAN, bat_priv,
 			"Other host probably restarted!\n");
 
 		bit_reset_window(seq_bits);

drivers/staging/batman-adv/hard-interface.c

@@ -443,6 +443,8 @@ static int batman_skb_recv_finish(struct sk_buff *skb)
 int batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
 	struct packet_type *ptype, struct net_device *orig_dev)
 {
+	/* FIXME: each orig_node->batman_if will be attached to a softif */
+	struct bat_priv *bat_priv = netdev_priv(soft_device);
 	struct batman_packet *batman_packet;
 	struct batman_if *batman_if;
 	struct net_device_stats *stats;
@@ -490,7 +492,7 @@ int batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
 	batman_packet = (struct batman_packet *)skb->data;
 
 	if (batman_packet->version != COMPAT_VERSION) {
-		bat_dbg(DBG_BATMAN,
+		bat_dbg(DBG_BATMAN, bat_priv,
 			"Drop packet: incompatible batman version (%i)\n",
 			batman_packet->version);
 		goto err_free;

drivers/staging/batman-adv/icmp_socket.c

@@ -154,6 +154,8 @@ static ssize_t bat_socket_read(struct file *file, char __user *buf,
 static ssize_t bat_socket_write(struct file *file, const char __user *buff,
 				size_t len, loff_t *off)
 {
+	/* FIXME: each orig_node->batman_if will be attached to a softif */
+	struct bat_priv *bat_priv = netdev_priv(soft_device);
 	struct socket_client *socket_client =
 		(struct socket_client *)file->private_data;
 	struct icmp_packet_rr icmp_packet;
@@ -164,7 +166,7 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
 	unsigned long flags;
 
 	if (len < sizeof(struct icmp_packet)) {
-		bat_dbg(DBG_BATMAN, "batman-adv:"
+		bat_dbg(DBG_BATMAN, bat_priv,
 			"Error - can't send packet from char device: "
 			"invalid packet size\n");
 		return -EINVAL;
@@ -180,14 +182,14 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
 		return -EFAULT;
 
 	if (icmp_packet.packet_type != BAT_ICMP) {
-		bat_dbg(DBG_BATMAN, "batman-adv:"
+		bat_dbg(DBG_BATMAN, bat_priv,
 			"Error - can't send packet from char device: "
 			"got bogus packet type (expected: BAT_ICMP)\n");
 		return -EINVAL;
 	}
 
 	if (icmp_packet.msg_type != ECHO_REQUEST) {
-		bat_dbg(DBG_BATMAN, "batman-adv:"
+		bat_dbg(DBG_BATMAN, bat_priv,
 			"Error - can't send packet from char device: "
 			"got bogus message type (expected: ECHO_REQUEST)\n");
 		return -EINVAL;