svc: Make close transport independent

Move sk_list and sk_ready to svc_xprt. This involves close because these
lists are walked by svcs when closing all their transports. So I combined
the moving of these lists to svc_xprt with making close transport independent.

The svc_force_sock_close has been changed to svc_close_all and takes a list
as an argument. This removes some svc internals knowledge from the svcs.

This code races with module removal and transport addition.

Thanks to Simon Holm Thøgersen for a compile fix.

Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
Acked-by: Neil Brown <neilb@suse.de>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Greg Banks <gnb@sgi.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Simon Holm Thøgersen <odie@cs.aau.dk>

fs/lockd/svc.c

@@ -221,10 +221,10 @@ lockd(struct svc_rqst *rqstp)
 
 static int find_xprt(struct svc_serv *serv, char *proto)
 {
-	struct svc_sock *svsk;
+	struct svc_xprt *xprt;
 	int found = 0;
-	list_for_each_entry(svsk, &serv->sv_permsocks, sk_list)
-		if (strcmp(svsk->sk_xprt.xpt_class->xcl_name, proto) == 0) {
+	list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list)
+		if (strcmp(xprt->xpt_class->xcl_name, proto) == 0) {
 			found = 1;
 			break;
 		}