[PATCH 4/5] genetlink: factor skb preparation out of ctrl_dumppolicy()

[Johannes Berg]

From: Johannes Berg <johannes.b...@intel.com>

We'll need this later for the per-op policy index dump.

Signed-off-by: Johannes Berg <johannes.b...@intel.com>
---
 net/netlink/genetlink.c | 26 +++++++++++++++++++-------
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index 42777749d4d8..0ab9549e30ee 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -1168,23 +1168,35 @@ static int ctrl_dumppolicy_start(struct 
netlink_callback *cb)
                                              op.maxattr);
 }
 
+static void *ctrl_dumppolicy_prep(struct sk_buff *skb,
+                                 struct netlink_callback *cb)
+{
+       struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
+       void *hdr;
+
+       hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
+                         cb->nlh->nlmsg_seq, &genl_ctrl,
+                         NLM_F_MULTI, CTRL_CMD_GETPOLICY);
+       if (!hdr)
+               return NULL;
+
+       if (nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, ctx->fam_id))
+               return NULL;
+
+       return hdr;
+}
+
 static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb)
 {
        struct ctrl_dump_policy_ctx *ctx = (void *)cb->ctx;
 
        while (netlink_policy_dump_loop(ctx->state)) {
-               void *hdr;
+               void *hdr = ctrl_dumppolicy_prep(skb, cb);
                struct nlattr *nest;
 
-               hdr = genlmsg_put(skb, NETLINK_CB(cb->skb).portid,
-                                 cb->nlh->nlmsg_seq, &genl_ctrl,
-                                 NLM_F_MULTI, CTRL_CMD_GETPOLICY);
                if (!hdr)
                        goto nla_put_failure;
 
-               if (nla_put_u16(skb, CTRL_ATTR_FAMILY_ID, ctx->fam_id))
-                       goto nla_put_failure;
-
                nest = nla_nest_start(skb, CTRL_ATTR_POLICY);
                if (!nest)
                        goto nla_put_failure;
-- 
2.26.2