genetlink: make policy common to family

Since maxattr is common, the policy can't really differ sanely,
so make it common as well.

The only user that did in fact manage to make a non-common policy
is taskstats, which has to be really careful about it (since it's
still using a common maxattr!). This is no longer supported, but
we can fake it using pre_doit.

This reduces the size of e.g. nl80211.o (which has lots of commands):

   text	   data	    bss	    dec	    hex	filename
 398745	  14323	   2240	 415308	  6564c	net/wireless/nl80211.o (before)
 397913	  14331	   2240	 414484	  65314	net/wireless/nl80211.o (after)
--------------------------------
   -832      +8       0    -824

Which is obviously just 8 bytes for each command, and an added 8
bytes for the new policy pointer. I'm not sure why the ops list is
counted as .text though.

Most of the code transformations were done using the following spatch:
    @ops@
    identifier OPS;
    expression POLICY;
    @@
    struct genl_ops OPS[] = {
    ...,
     {
    -	.policy = POLICY,
     },
    ...
    };

    @@
    identifier ops.OPS;
    expression ops.POLICY;
    identifier fam;
    expression M;
    @@
    struct genl_family fam = {
            .ops = OPS,
            .maxattr = M,
    +       .policy = POLICY,
            ...
    };

This also gets rid of devlink_nl_cmd_region_read_dumpit() accessing
the cb->data as ops, which we want to change in a later genl patch.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 2 insertions, 31 deletions

diff --git a/net/ieee802154/ieee802154.h b/net/ieee802154/ieee802154.h
index a5d7515b7f62..bc147bc8e36a 100644
--- a/net/ieee802154/ieee802154.h
+++ b/net/ieee802154/ieee802154.h
@@ -20,7 +20,6 @@ void ieee802154_nl_exit(void);
 #define IEEE802154_OP(_cmd, _func)			\
 	{						\
 		.cmd	= _cmd,				\
-		.policy	= ieee802154_policy,		\
 		.doit	= _func,			\
 		.dumpit	= NULL,				\
 		.flags	= GENL_ADMIN_PERM,		\
@@ -29,7 +28,6 @@ void ieee802154_nl_exit(void);
 #define IEEE802154_DUMP(_cmd, _func, _dump)		\
 	{						\
 		.cmd	= _cmd,				\
-		.policy	= ieee802154_policy,		\
 		.doit	= _func,			\
 		.dumpit	= _dump,			\
 	}
diff --git a/net/ieee802154/netlink.c b/net/ieee802154/netlink.c
index 96636e3b7aa9..098d67439b6d 100644
--- a/net/ieee802154/netlink.c
+++ b/net/ieee802154/netlink.c
@@ -136,6 +136,7 @@ struct genl_family nl802154_family __ro_after_init = {
 	.name		= IEEE802154_NL_NAME,
 	.version	= 1,
 	.maxattr	= IEEE802154_ATTR_MAX,
+	.policy		= ieee802154_policy,
 	.module		= THIS_MODULE,
 	.ops		= ieee802154_ops,
 	.n_ops		= ARRAY_SIZE(ieee802154_ops),
diff --git a/net/ieee802154/nl802154.c b/net/ieee802154/nl802154.c
index 99f6c254ea77..308370cfd668 100644
--- a/net/ieee802154/nl802154.c
+++ b/net/ieee802154/nl802154.c
@@ -2220,7 +2220,6 @@ static const struct genl_ops nl802154_ops[] = {
 		.doit = nl802154_get_wpan_phy,
 		.dumpit = nl802154_dump_wpan_phy,
 		.done = nl802154_dump_wpan_phy_done,
-		.policy = nl802154_policy,
 		/* can be retrieved by unprivileged users */
 		.internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2229,7 +2228,6 @@ static const struct genl_ops nl802154_ops[] = {
 		.cmd = NL802154_CMD_GET_INTERFACE,
 		.doit = nl802154_get_interface,
 		.dumpit = nl802154_dump_interface,
-		.policy = nl802154_policy,
 		/* can be retrieved by unprivileged users */
 		.internal_flags = NL802154_FLAG_NEED_WPAN_DEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2237,7 +2235,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_NEW_INTERFACE,
 		.doit = nl802154_new_interface,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2245,7 +2242,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_DEL_INTERFACE,
 		.doit = nl802154_del_interface,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_WPAN_DEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2253,7 +2249,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_CHANNEL,
 		.doit = nl802154_set_channel,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2261,7 +2256,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_CCA_MODE,
 		.doit = nl802154_set_cca_mode,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2269,7 +2263,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_CCA_ED_LEVEL,
 		.doit = nl802154_set_cca_ed_level,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2277,7 +2270,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_TX_POWER,
 		.doit = nl802154_set_tx_power,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2285,7 +2277,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_WPAN_PHY_NETNS,
 		.doit = nl802154_wpan_phy_netns,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2293,7 +2284,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_PAN_ID,
 		.doit = nl802154_set_pan_id,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2301,7 +2291,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_SHORT_ADDR,
 		.doit = nl802154_set_short_addr,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2309,7 +2298,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_BACKOFF_EXPONENT,
 		.doit = nl802154_set_backoff_exponent,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2317,7 +2305,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_MAX_CSMA_BACKOFFS,
 		.doit = nl802154_set_max_csma_backoffs,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2325,7 +2312,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_MAX_FRAME_RETRIES,
 		.doit = nl802154_set_max_frame_retries,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2333,7 +2319,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_LBT_MODE,
 		.doit = nl802154_set_lbt_mode,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2341,7 +2326,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_ACKREQ_DEFAULT,
 		.doit = nl802154_set_ackreq_default,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2350,7 +2334,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_SET_SEC_PARAMS,
 		.doit = nl802154_set_llsec_params,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2359,7 +2342,6 @@ static const struct genl_ops nl802154_ops[] = {
 		.cmd = NL802154_CMD_GET_SEC_KEY,
 		/* TODO .doit by matching key id? */
 		.dumpit = nl802154_dump_llsec_key,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2367,7 +2349,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_NEW_SEC_KEY,
 		.doit = nl802154_add_llsec_key,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2375,7 +2356,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_DEL_SEC_KEY,
 		.doit = nl802154_del_llsec_key,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2385,7 +2365,6 @@ static const struct genl_ops nl802154_ops[] = {
 		.cmd = NL802154_CMD_GET_SEC_DEV,
 		/* TODO .doit by matching extended_addr? */
 		.dumpit = nl802154_dump_llsec_dev,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2393,7 +2372,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_NEW_SEC_DEV,
 		.doit = nl802154_add_llsec_dev,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2401,7 +2379,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_DEL_SEC_DEV,
 		.doit = nl802154_del_llsec_dev,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2411,7 +2388,6 @@ static const struct genl_ops nl802154_ops[] = {
 		.cmd = NL802154_CMD_GET_SEC_DEVKEY,
 		/* TODO doit by matching ??? */
 		.dumpit = nl802154_dump_llsec_devkey,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2419,7 +2395,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_NEW_SEC_DEVKEY,
 		.doit = nl802154_add_llsec_devkey,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2427,7 +2402,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_DEL_SEC_DEVKEY,
 		.doit = nl802154_del_llsec_devkey,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2436,7 +2410,6 @@ static const struct genl_ops nl802154_ops[] = {
 		.cmd = NL802154_CMD_GET_SEC_LEVEL,
 		/* TODO .doit by matching frame_type? */
 		.dumpit = nl802154_dump_llsec_seclevel,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2444,7 +2417,6 @@ static const struct genl_ops nl802154_ops[] = {
 	{
 		.cmd = NL802154_CMD_NEW_SEC_LEVEL,
 		.doit = nl802154_add_llsec_seclevel,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2453,7 +2425,6 @@ static const struct genl_ops nl802154_ops[] = {
 		.cmd = NL802154_CMD_DEL_SEC_LEVEL,
 		/* TODO match frame_type only? */
 		.doit = nl802154_del_llsec_seclevel,
-		.policy = nl802154_policy,
 		.flags = GENL_ADMIN_PERM,
 		.internal_flags = NL802154_FLAG_NEED_NETDEV |
 				  NL802154_FLAG_NEED_RTNL,
@@ -2466,6 +2437,7 @@ static struct genl_family nl802154_fam __ro_after_init = {
 	.hdrsize = 0,			/* no private header */
 	.version = 1,			/* no particular meaning now */
 	.maxattr = NL802154_ATTR_MAX,
+	.policy = nl802154_policy,
 	.netnsok = true,
 	.pre_doit = nl802154_pre_doit,
 	.post_doit = nl802154_post_doit,