[B.A.T.M.A.N.] [PATCHv13 4/4] batman-adv: Add debugfs table for mcast flags

["Linus Lüssing" <linus.luessing@c0d3.blue>]

This patch adds a debugfs table with originators and their according
multicast flags to help users figure out why multicast optimizations
might be enabled or disabled for them.

Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
---
 net/batman-adv/debugfs.c   |   21 +++++++++
 net/batman-adv/multicast.c |  101 ++++++++++++++++++++++++++++++++++++++++++++
 net/batman-adv/multicast.h |    2 +
 3 files changed, 124 insertions(+)

diff --git a/net/batman-adv/debugfs.c b/net/batman-adv/debugfs.c
index 3dc5208..2cbff01 100644
--- a/net/batman-adv/debugfs.c
+++ b/net/batman-adv/debugfs.c
@@ -48,6 +48,7 @@
 #include "distributed-arp-table.h"
 #include "gateway_client.h"
 #include "icmp_socket.h"
+#include "multicast.h"
 #include "network-coding.h"
 #include "originator.h"
 #include "translation-table.h"
@@ -363,6 +364,20 @@ static int batadv_nc_nodes_open(struct inode *inode, struct file *file)
 }
 #endif
 
+#ifdef CONFIG_BATMAN_ADV_MCAST
+/**
+ * batadv_mcast_flags_open - prepare file handler for reads from mcast_flags
+ * @inode: inode which was opened
+ * @file: file handle to be initialized
+ */
+static int batadv_mcast_flags_open(struct inode *inode, struct file *file)
+{
+	struct net_device *net_dev = (struct net_device *)inode->i_private;
+
+	return single_open(file, batadv_mcast_flags_seq_print_text, net_dev);
+}
+#endif
+
 #define BATADV_DEBUGINFO(_name, _mode, _open)		\
 struct batadv_debuginfo batadv_debuginfo_##_name = {	\
 	.attr = { .name = __stringify(_name),		\
@@ -404,6 +419,9 @@ static BATADV_DEBUGINFO(transtable_local, S_IRUGO,
 #ifdef CONFIG_BATMAN_ADV_NC
 static BATADV_DEBUGINFO(nc_nodes, S_IRUGO, batadv_nc_nodes_open);
 #endif
+#ifdef CONFIG_BATMAN_ADV_MCAST
+static BATADV_DEBUGINFO(mcast_flags, S_IRUGO, batadv_mcast_flags_open);
+#endif
 
 static struct batadv_debuginfo *batadv_mesh_debuginfos[] = {
 	&batadv_debuginfo_neighbors,
@@ -421,6 +439,9 @@ static struct batadv_debuginfo *batadv_mesh_debuginfos[] = {
 #ifdef CONFIG_BATMAN_ADV_NC
 	&batadv_debuginfo_nc_nodes,
 #endif
+#ifdef CONFIG_BATMAN_ADV_MCAST
+	&batadv_debuginfo_mcast_flags,
+#endif
 	NULL,
 };
 
diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
index 148344e..0d732d7 100644
--- a/net/batman-adv/multicast.c
+++ b/net/batman-adv/multicast.c
@@ -50,6 +50,8 @@
 #include <net/ipv6.h>
 #include <net/mld.h>
 
+#include "hard-interface.h"
+#include "hash.h"
 #include "packet.h"
 #include "translation-table.h"
 
@@ -1127,6 +1129,105 @@ void batadv_mcast_init(struct batadv_priv *bat_priv)
 }
 
 /**
+ * batadv_mcast_flags_print_header - print own mcast flags to debugfs table
+ * @bat_priv: the bat priv with all the soft interface information
+ * @seq: debugfs table seq_file struct
+ *
+ * Prints our own multicast flags including a more specific reason why
+ * they are set, that is prints the bridge and querier state too, to
+ * the debugfs table specified via @seq.
+ */
+static void batadv_mcast_flags_print_header(struct batadv_priv *bat_priv,
+					    struct seq_file *seq)
+{
+	u8 flags = bat_priv->mcast.flags;
+	char querier4, querier6, shadowing4, shadowing6;
+	bool bridged = bat_priv->mcast.bridged;
+
+	if (bridged) {
+		querier4 = bat_priv->mcast.querier_ipv4.exists ? '.' : '4';
+		querier6 = bat_priv->mcast.querier_ipv6.exists ? '.' : '6';
+		shadowing4 = bat_priv->mcast.querier_ipv4.shadowing ? '4' : '.';
+		shadowing6 = bat_priv->mcast.querier_ipv6.shadowing ? '6' : '.';
+	} else {
+		querier4 = '?';
+		querier6 = '?';
+		shadowing4 = '?';
+		shadowing6 = '?';
+	}
+
+	seq_printf(seq, "Multicast flags (own flags: [%c%c%c])\n",
+		   flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES ? 'U' : '.',
+		   flags & BATADV_MCAST_WANT_ALL_IPV4 ? '4' : '.',
+		   flags & BATADV_MCAST_WANT_ALL_IPV6 ? '6' : '.');
+	seq_printf(seq, "* Bridged [U]\t\t\t\t%c\n", bridged ? 'U' : '.');
+	seq_printf(seq, "* No IGMP/MLD Querier [4/6]:\t\t%c/%c\n",
+		   querier4, querier6);
+	seq_printf(seq, "* Shadowing IGMP/MLD Querier [4/6]:\t%c/%c\n",
+		   shadowing4, shadowing6);
+	seq_puts(seq, "-------------------------------------------\n");
+	seq_printf(seq, "       %-10s %s\n", "Originator", "Flags");
+}
+
+/**
+ * batadv_mcast_flags_seq_print_text - print the mcast flags of other nodes
+ * @seq: seq file to print on
+ * @offset: not used
+ *
+ * This prints a table of (primary) originators and their according
+ * multicast flags, including (in the header) our own.
+ */
+int batadv_mcast_flags_seq_print_text(struct seq_file *seq, void *offset)
+{
+	struct net_device *net_dev = (struct net_device *)seq->private;
+	struct batadv_priv *bat_priv = netdev_priv(net_dev);
+	struct batadv_hard_iface *primary_if;
+	struct batadv_hashtable *hash = bat_priv->orig_hash;
+	struct batadv_orig_node *orig_node;
+	struct hlist_head *head;
+	u8 flags;
+	u32 i;
+
+	primary_if = batadv_seq_print_text_primary_if_get(seq);
+	if (!primary_if)
+		return 0;
+
+	batadv_mcast_flags_print_header(bat_priv, seq);
+
+	for (i = 0; i < hash->size; i++) {
+		head = &hash->table[i];
+
+		rcu_read_lock();
+		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
+			if (!(orig_node->capa_initialized &
+			      BATADV_ORIG_CAPA_HAS_MCAST))
+				continue;
+
+			flags = orig_node->mcast_flags;
+
+			if (!(orig_node->capabilities &
+			      BATADV_ORIG_CAPA_HAS_MCAST)) {
+				seq_printf(seq, "%pM -\n", orig_node->orig);
+				continue;
+			}
+
+			seq_printf(seq, "%pM [%c%c%c]\n", orig_node->orig,
+				   (flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES ?
+				    'U' : '.'),
+				   (flags & BATADV_MCAST_WANT_ALL_IPV4 ?
+				    '4' : '.'),
+				   (flags & BATADV_MCAST_WANT_ALL_IPV6 ?
+				    '6' : '.'));
+		}
+		rcu_read_unlock();
+	}
+
+	batadv_hardif_put(primary_if);
+
+	return 0;
+}
+
+/**
  * batadv_mcast_free - free the multicast optimizations structures
  * @bat_priv: the bat priv with all the soft interface information
  */
diff --git a/net/batman-adv/multicast.h b/net/batman-adv/multicast.h
index 80bceec..df744c6 100644
--- a/net/batman-adv/multicast.h
+++ b/net/batman-adv/multicast.h
@@ -46,6 +46,8 @@ batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb,
 
 void batadv_mcast_init(struct batadv_priv *bat_priv);
 
+int batadv_mcast_flags_seq_print_text(struct seq_file *seq, void *offset);
+
 void batadv_mcast_free(struct batadv_priv *bat_priv);
 
 void batadv_mcast_purge_orig(struct batadv_orig_node *orig_node);
-- 
1.7.10.4