[PATCH 1/2] net: netrom: mark expected switch fall-throughs

[PATCH 1/2] net: netrom: mark expected switch fall-throughs

[Gustavo A. R. Silva]

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
---
This code was tested by compilation only (GCC 7.2.0 was used).
Please, verify if the actual intention of the code is to fall through.

 net/netrom/nr_route.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c
index 0c59354..fc9cadc 100644
--- a/net/netrom/nr_route.c
+++ b/net/netrom/nr_route.c
@@ -279,6 +279,7 @@ static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
 			nr_node->routes[1] = nr_node->routes[2];
 			nr_node->routes[2] = nr_route;
 		}
+		/* fall through */
 	case 2:
 		if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
 			switch (nr_node->which) {
@@ -384,6 +385,7 @@ static int nr_del_node(ax25_address *callsign, ax25_address *neighbour, struct n
 				switch (i) {
 				case 0:
 					nr_node->routes[0] = nr_node->routes[1];
+					/* fall through */
 				case 1:
 					nr_node->routes[1] = nr_node->routes[2];
 				case 2:
@@ -506,7 +508,7 @@ static int nr_dec_obs(void)
 				switch (i) {
 				case 0:
 					s->routes[0] = s->routes[1];
-					/* Fallthrough */
+					/* fall through */
 				case 1:
 					s->routes[1] = s->routes[2];
 				case 2:
@@ -553,6 +555,7 @@ void nr_rt_device_down(struct net_device *dev)
 						switch (i) {
 						case 0:
 							t->routes[0] = t->routes[1];
+							/* fall through */
 						case 1:
 							t->routes[1] = t->routes[2];
 						case 2:
-- 
2.7.4

[PATCH 2/2] net: netrom: refactor code in nr_add_node

[Gustavo A. R. Silva]

Code refactoring in order to make the code easier to read and maintain.

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
---
This code was tested by compilation only (GCC 7.2.0 was used).

 net/netrom/nr_route.c | 63 ++++++++++++++++-----------------------------------
 1 file changed, 20 insertions(+), 43 deletions(-)

diff --git a/net/netrom/nr_route.c b/net/netrom/nr_route.c
index fc9cadc..1e5165f 100644
--- a/net/netrom/nr_route.c
+++ b/net/netrom/nr_route.c
@@ -80,6 +80,23 @@ static struct nr_neigh *nr_neigh_get_dev(ax25_address *callsign,
 
 static void nr_remove_neigh(struct nr_neigh *);
 
+/*      re-sort the routes in quality order.    */
+static inline void re_sort_routes(struct nr_node *nr_node, int ix_x, int ix_y)
+{
+	struct nr_route nr_route;
+
+	if (nr_node->routes[ix_y].quality > nr_node->routes[ix_x].quality) {
+		if (nr_node->which == ix_x)
+			nr_node->which = ix_y;
+		else if (nr_node->which == ix_y)
+			nr_node->which = ix_x;
+
+		nr_route              = nr_node->routes[ix_x];
+		nr_node->routes[ix_x] = nr_node->routes[ix_y];
+		nr_node->routes[ix_y] = nr_route;
+	}
+}
+
 /*
  *	Add a new route to a node, and in the process add the node and the
  *	neighbour if it is new.
@@ -90,7 +107,6 @@ static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
 {
 	struct nr_node  *nr_node;
 	struct nr_neigh *nr_neigh;
-	struct nr_route nr_route;
 	int i, found;
 	struct net_device *odev;
 
@@ -251,50 +267,11 @@ static int __must_check nr_add_node(ax25_address *nr, const char *mnemonic,
 	/* Now re-sort the routes in quality order */
 	switch (nr_node->count) {
 	case 3:
-		if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
-			switch (nr_node->which) {
-			case 0:
-				nr_node->which = 1;
-				break;
-			case 1:
-				nr_node->which = 0;
-				break;
-			}
-			nr_route           = nr_node->routes[0];
-			nr_node->routes[0] = nr_node->routes[1];
-			nr_node->routes[1] = nr_route;
-		}
-		if (nr_node->routes[2].quality > nr_node->routes[1].quality) {
-			switch (nr_node->which) {
-			case 1:  nr_node->which = 2;
-				break;
-
-			case 2:  nr_node->which = 1;
-				break;
-
-			default:
-				break;
-			}
-			nr_route           = nr_node->routes[1];
-			nr_node->routes[1] = nr_node->routes[2];
-			nr_node->routes[2] = nr_route;
-		}
+		re_sort_routes(nr_node, 0, 1);
+		re_sort_routes(nr_node, 1, 2);
 		/* fall through */
 	case 2:
-		if (nr_node->routes[1].quality > nr_node->routes[0].quality) {
-			switch (nr_node->which) {
-			case 0:  nr_node->which = 1;
-				break;
-
-			case 1:  nr_node->which = 0;
-				break;
-
-			default: break;
-			}
-			nr_route           = nr_node->routes[0];
-			nr_node->routes[0] = nr_node->routes[1];
-			nr_node->routes[1] = nr_route;
-			}
+		re_sort_routes(nr_node, 0, 1);
 	case 1:
 		break;
 	}
-- 
2.7.4