batman-adv: make the TT CRC logic VLAN specific

This change allows nodes to handle the TT table on a
per-VLAN basis. This is needed because nodes may have to
store only some of the global entries advertised by another
node.

In this scenario such nodes would re-create only a partial
global table and would not be able to compute a correct CRC
anymore.

This patch splits the logic and introduces one CRC per VLAN.
In this way a node fetching only some entries belonging to
some VLANs is still able to compute the needed CRCs and
still check the table correctness.

With this patch the shape of the TVLV-TT is changed too
because now a node needs to advertise all the CRCs of all
the VLANs that it is wired to.

The debug output of the local Translation Table now shows
the CRC along with each entry since there is not a common
value for the entire table anymore.

Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>

1 files changed, 33 insertions, 8 deletions

diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index bd95d612260c..ff53933b5a59 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -107,6 +107,32 @@ struct batadv_frag_list_entry {
 };
 
 /**
+ * struct batadv_vlan_tt - VLAN specific TT attributes
+ * @crc: CRC32 checksum of the entries belonging to this vlan
+ * @num_entries: number of TT entries for this VLAN
+ */
+struct batadv_vlan_tt {
+	uint32_t crc;
+	atomic_t num_entries;
+};
+
+/**
+ * batadv_orig_node_vlan - VLAN specific data per orig_node
+ * @vid: the VLAN identifier
+ * @tt: VLAN specific TT attributes
+ * @list: list node for orig_node::vlan_list
+ * @refcount: number of context where this object is currently in use
+ * @rcu: struct used for freeing in a RCU-safe manner
+ */
+struct batadv_orig_node_vlan {
+	unsigned short vid;
+	struct batadv_vlan_tt tt;
+	struct list_head list;
+	atomic_t refcount;
+	struct rcu_head rcu;
+};
+
+/**
  * struct batadv_orig_node - structure for orig_list maintaining nodes of mesh
  * @orig: originator ethernet address
  * @primary_addr: hosts primary interface address
@@ -120,12 +146,10 @@ struct batadv_frag_list_entry {
  * @batman_seqno_reset: time when the batman seqno window was reset
  * @capabilities: announced capabilities of this originator
  * @last_ttvn: last seen translation table version number
- * @tt_crc: CRC of the translation table
  * @tt_buff: last tt changeset this node received from the orig node
  * @tt_buff_len: length of the last tt changeset this node received from the
  *  orig node
  * @tt_buff_lock: lock that protects tt_buff and tt_buff_len
- * @tt_size: number of global TT entries announced by the orig node
  * @tt_initialised: bool keeping track of whether or not this node have received
  *  any translation table information from the orig node yet
  * @tt_lock: prevents from updating the table while reading it. Table update is
@@ -154,6 +178,9 @@ struct batadv_frag_list_entry {
  * @in_coding_list_lock: protects in_coding_list
  * @out_coding_list_lock: protects out_coding_list
  * @fragments: array with heads for fragment chains
+ * @vlan_list: a list of orig_node_vlan structs, one per VLAN served by the
+ *  originator represented by this object
+ * @vlan_list_lock: lock protecting vlan_list
  */
 struct batadv_orig_node {
 	uint8_t orig[ETH_ALEN];
@@ -169,11 +196,9 @@ struct batadv_orig_node {
 	unsigned long batman_seqno_reset;
 	uint8_t capabilities;
 	atomic_t last_ttvn;
-	uint32_t tt_crc;
 	unsigned char *tt_buff;
 	int16_t tt_buff_len;
 	spinlock_t tt_buff_lock; /* protects tt_buff & tt_buff_len */
-	atomic_t tt_size;
 	bool tt_initialised;
 	/* prevents from changing the table while reading it */
 	spinlock_t tt_lock;
@@ -203,6 +228,8 @@ struct batadv_orig_node {
 	spinlock_t out_coding_list_lock; /* Protects out_coding_list */
 #endif
 	struct batadv_frag_table_entry fragments[BATADV_FRAG_BUFFER_COUNT];
+	struct list_head vlan_list;
+	spinlock_t vlan_list_lock; /* protects vlan_list */
 };
 
 /**
@@ -389,8 +416,6 @@ enum batadv_counters {
  * @changes_list_lock: lock protecting changes_list
  * @req_list_lock: lock protecting req_list
  * @roam_list_lock: lock protecting roam_list
- * @local_entry_num: number of entries in the local hash table
- * @local_crc: Checksum of the local table, recomputed before sending a new OGM
  * @last_changeset: last tt changeset this host has generated
  * @last_changeset_len: length of last tt changeset this host has generated
  * @last_changeset_lock: lock protecting last_changeset & last_changeset_len
@@ -413,8 +438,6 @@ struct batadv_priv_tt {
 	spinlock_t changes_list_lock; /* protects changes */
 	spinlock_t req_list_lock; /* protects req_list */
 	spinlock_t roam_list_lock; /* protects roam_list */
-	atomic_t local_entry_num;
-	uint32_t local_crc;
 	unsigned char *last_changeset;
 	int16_t last_changeset_len;
 	/* protects last_changeset & last_changeset_len */
@@ -548,6 +571,7 @@ struct batadv_priv_nc {
  * @vid: VLAN identifier
  * @kobj: kobject for sysfs vlan subdirectory
  * @ap_isolation: AP isolation state
+ * @tt: TT private attributes (VLAN specific)
  * @list: list node for bat_priv::softif_vlan_list
  * @refcount: number of context where this object is currently in use
  * @rcu: struct used for freeing in a RCU-safe manner
@@ -556,6 +580,7 @@ struct batadv_softif_vlan {
 	unsigned short vid;
 	struct kobject *kobj;
 	atomic_t ap_isolation;		/* boolean */
+	struct batadv_vlan_tt tt;
 	struct hlist_node list;
 	atomic_t refcount;
 	struct rcu_head rcu;