genetlink: Build a generic netlink family module alias
Generic netlink searches for -type- formatted aliases when requesting a module to
fulfill a protocol request (i.e. net-pf-16-proto-16-type-<x>, where x is a type
value). However generic netlink protocols have no well defined type numbers,
they have string names. Modify genl_ctrl_getfamily to request an alias in the
format net-pf-16-proto-16-family-<x> instead, where x is a generic string, and
add a macro that builds on the previously added MODULE_ALIAS_NET_PF_PROTO_NAME
macro to allow modules to specifify those generic strings.
Note, l2tp previously hacked together an net-pf-16-proto-16-type-l2tp alias
using the MODULE_ALIAS macro, with these updates we can convert that to use the
PROTO_NAME macro.
Signed-off-by: Neil Horman <[email protected]>
CC: Eric Dumazet <[email protected]>
CC: James Chapman <[email protected]>
CC: David Miller <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
diff --git a/include/linux/genetlink.h b/include/linux/genetlink.h
index 73c28de..7a11401 100644
--- a/include/linux/genetlink.h
+++ b/include/linux/genetlink.h
@@ -110,6 +110,9 @@
#define genl_dereference(p) \
rcu_dereference_protected(p, lockdep_genl_is_held())
+#define MODULE_ALIAS_GENL_FAMILY(family)\
+ MODULE_ALIAS_NET_PF_PROTO_NAME(PF_NETLINK, NETLINK_GENERIC, "-family-" family)
+
#endif /* __KERNEL__ */
#endif /* __LINUX_GENERIC_NETLINK_H */
diff --git a/net/l2tp/l2tp_netlink.c b/net/l2tp/l2tp_netlink.c
index 85772643..ddc553e 100644
--- a/net/l2tp/l2tp_netlink.c
+++ b/net/l2tp/l2tp_netlink.c
@@ -923,5 +923,4 @@
MODULE_DESCRIPTION("L2TP netlink");
MODULE_LICENSE("GPL");
MODULE_VERSION("1.0");
-MODULE_ALIAS("net-pf-" __stringify(PF_NETLINK) "-proto-" \
- __stringify(NETLINK_GENERIC) "-type-" "l2tp");
+MODULE_ALIAS_GENL_FAMILY("l2tp");
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index 8340ace..2cc7c1e 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -836,7 +836,7 @@
#ifdef CONFIG_MODULES
if (res == NULL) {
genl_unlock();
- request_module("net-pf-%d-proto-%d-type-%s",
+ request_module("net-pf-%d-proto-%d-family-%s",
PF_NETLINK, NETLINK_GENERIC, name);
genl_lock();
res = genl_family_find_byname(name);
