flow, tcp: Generalise TCP hash table to general flow hash table

Move the data structures and helper functions for the TCP hash table to
flow.c, making it a general hash table indexing sides of flows.  This is
largely code motion and straightforward renames.  There are two semantic
changes:

 * flow_lookup_af() now needs to verify that the entry has a matching
   protocol and interface as well as matching addresses and ports.

 * We double the size of the hash table, because it's now at least
   theoretically possible for both sides of each flow to be hashed.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

1 files changed, 7 insertions, 4 deletions

diff --git a/flow.h b/flow.h
index a0550dc..fcb4121 100644
--- a/flow.h
+++ b/flow.h
@@ -164,10 +164,6 @@ static inline bool flowside_eq(const struct flowside *left,
 	       left->fport == right->fport;
 }
 
-void flowside_from_af(struct flowside *side, sa_family_t af,
-		      const void *eaddr, in_port_t eport,
-		      const void *faddr, in_port_t fport);
-
 /**
  * struct flow_common - Common fields for packet flows
  * @state:	State of the flow table entry
@@ -233,6 +229,13 @@ static inline bool flow_sidx_eq(flow_sidx_t a, flow_sidx_t b)
 	return (a.flowi == b.flowi) && (a.sidei == b.sidei);
 }
 
+void flow_hash_insert(const struct ctx *c, flow_sidx_t sidx);
+void flow_hash_remove(const struct ctx *c, flow_sidx_t sidx);
+flow_sidx_t flow_lookup_af(const struct ctx *c,
+			   uint8_t proto, uint8_t pif, sa_family_t af,
+			   const void *eaddr, const void *faddr,
+			   in_port_t eport, in_port_t fport);
+
 union flow;
 
 void flow_init(void);