mptcp: fullmesh: raise addresses limit from 8 to 16

This allows fullmesh path manager to use up-to 16 addresses instead of
the previous limit of 8.

Note that this increases the size of 'struct mptcp_cb' considerably.

Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>

include/net/mptcp.h

@@ -329,7 +329,7 @@ struct mptcp_cb {
 	__u32	mptcp_loc_token;
 	__u32	mptcp_rem_token;
 
-#define MPTCP_PM_SIZE 608
+#define MPTCP_PM_SIZE 720
 	u8 mptcp_pm[MPTCP_PM_SIZE] __aligned(8);
 	const struct mptcp_pm_ops *pm_ops;
 

net/mptcp/mptcp_fullmesh.c

@@ -20,32 +20,32 @@ enum {
 /* Max number of local or remote addresses we can store.
  * When changing, see the bitfield below in fullmesh_rem4/6.
  */
-#define MPTCP_MAX_ADDR	8
+#define MPTCP_MAX_ADDR	16
 
 struct fullmesh_rem4 {
 	u8		rem4_id;
-	u8		bitfield;
-	u8		retry_bitfield;
+	u16		bitfield;
+	u16		retry_bitfield;
 	__be16		port;
 	struct in_addr	addr;
 };
 
 struct fullmesh_rem6 {
 	u8		rem6_id;
-	u8		bitfield;
-	u8		retry_bitfield;
+	u16		bitfield;
+	u16		retry_bitfield;
 	__be16		port;
 	struct in6_addr	addr;
 };
 
 struct mptcp_loc_addr {
 	struct mptcp_loc4 locaddr4[MPTCP_MAX_ADDR];
-	u8 loc4_bits;
-	u8 next_v4_index;
+	u16 loc4_bits;
+	u16 next_v4_index;
 
 	struct mptcp_loc6 locaddr6[MPTCP_MAX_ADDR];
-	u8 loc6_bits;
-	u8 next_v6_index;
+	u16 loc6_bits;
+	u16 next_v6_index;
 	struct rcu_head rcu;
 };
 
@@ -71,13 +71,13 @@ struct fullmesh_priv {
 	struct mptcp_cb *mpcb;
 
 	u16 remove_addrs; /* Addresses to remove */
-	u8 announced_addrs_v4; /* IPv4 Addresses we did announce */
-	u8 announced_addrs_v6; /* IPv6 Addresses we did announce */
+	u16 announced_addrs_v4; /* IPv4 Addresses we did announce */
+	u16 announced_addrs_v6; /* IPv6 Addresses we did announce */
 
 	u8	add_addr; /* Are we sending an add_addr? */
 
-	u8 rem4_bits;
-	u8 rem6_bits;
+	u16 rem4_bits;
+	u16 rem6_bits;
 
 	/* Have we established the additional subflows for primary pair? */
 	u8 first_pair:1;
@@ -115,12 +115,12 @@ static struct fullmesh_priv *fullmesh_get_priv(const struct mptcp_cb *mpcb)
 }
 
 /* Find the first free index in the bitfield */
-static int __mptcp_find_free_index(u8 bitfield, u8 base)
+static int __mptcp_find_free_index(u16 bitfield, u16 base)
 {
 	int i;
 
 	/* There are anyways no free bits... */
-	if (bitfield == 0xff)
+	if (bitfield == 0xffff)
 		goto exit;
 
 	i = ffs(~(bitfield >> base)) - 1;
@@ -136,7 +136,7 @@ static int __mptcp_find_free_index(u8 bitfield, u8 base)
 	return -1;
 }
 
-static int mptcp_find_free_index(u8 bitfield)
+static int mptcp_find_free_index(u16 bitfield)
 {
 	return __mptcp_find_free_index(bitfield, 0);
 }
@@ -510,7 +510,7 @@ static void create_subflow_worker(struct work_struct *work)
 
 	mptcp_for_each_bit_set(fmp->rem4_bits, i) {
 		struct fullmesh_rem4 *rem;
-		u8 remaining_bits;
+		u16 remaining_bits;
 
 		rem = &fmp->remaddr4[i];
 		remaining_bits = ~(rem->bitfield) & mptcp_local->loc4_bits;
@@ -558,7 +558,7 @@ static void create_subflow_worker(struct work_struct *work)
 	}
 	mptcp_for_each_bit_set(fmp->rem6_bits, i) {
 		struct fullmesh_rem6 *rem;
-		u8 remaining_bits;
+		u16 remaining_bits;
 
 		rem = &fmp->remaddr6[i];
 		remaining_bits = ~(rem->bitfield) & mptcp_local->loc6_bits;
@@ -646,7 +646,7 @@ static int mptcp_find_address(const struct mptcp_loc_addr *mptcp_local,
 			      int if_idx)
 {
 	int i;
-	u8 loc_bits;
+	u16 loc_bits;
 	bool found = false;
 
 	if (family == AF_INET)
@@ -680,7 +680,7 @@ static int mptcp_find_address_transp(const struct mptcp_loc_addr *mptcp_local,
 				     sa_family_t family, int if_idx)
 {
 	bool found = false;
-	u8 loc_bits;
+	u16 loc_bits;
 	int i;
 
 	if (family == AF_INET)
@@ -1564,7 +1564,7 @@ static void full_mesh_addr_signal(struct sock *sk, unsigned *size,
 	struct mptcp_loc_addr *mptcp_local;
 	struct mptcp_fm_ns *fm_ns = fm_get_ns(sock_net(sk));
 	int remove_addr_len;
-	u8 unannouncedv4 = 0, unannouncedv6 = 0;
+	u16 unannouncedv4 = 0, unannouncedv6 = 0;
 	bool meta_v4 = meta_sk->sk_family == AF_INET;
 
 	mpcb->addr_signal = 0;