rtnetlink: Compute and store minimum ifinfo dump size

The message size allocated for rtnl ifinfo dumps was limited to
a single page.  This is not enough for additional interface info
available with devices that support SR-IOV and caused a bug in
which VF info would not be displayed if more than approximately
40 VFs were created per interface.

Implement a new function pointer for the rtnl_register service that will
calculate the amount of data required for the ifinfo dump and allocate
enough data to satisfy the request.

Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index 4093ca78cf60..678f1ffaf843 100644
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -6,11 +6,14 @@
 
 typedef int (*rtnl_doit_func)(struct sk_buff *, struct nlmsghdr *, void *);
 typedef int (*rtnl_dumpit_func)(struct sk_buff *, struct netlink_callback *);
+typedef u16 (*rtnl_calcit_func)(struct sk_buff *);
 
 extern int      __rtnl_register(int protocol, int msgtype,
-                                rtnl_doit_func, rtnl_dumpit_func);
+                                rtnl_doit_func, rtnl_dumpit_func,
+                                rtnl_calcit_func);
 extern void     rtnl_register(int protocol, int msgtype,
-                              rtnl_doit_func, rtnl_dumpit_func);
+                              rtnl_doit_func, rtnl_dumpit_func,
+                              rtnl_calcit_func);
 extern int      rtnl_unregister(int protocol, int msgtype);
 extern void     rtnl_unregister_all(int protocol);