On 09/05/2018 05:54 AM, Cong Wang wrote: > __tipc_nl_compat_dumpit() uses a netlink_callback on stack, > so the only way to align it with other ->dumpit() call path > is calling tipc_dump_start() and tipc_dump_done() directly > inside it. Otherwise ->dumpit() would always get NULL from > cb->args[]. > > But tipc_dump_start() uses sock_net(cb->skb->sk) to retrieve > net pointer, the cb->skb here doesn't set skb->sk, the net pointer > is saved in msg->net instead, so introduce a helper function > __tipc_dump_start() to pass in msg->net. > > Ying pointed out cb->args[0...3] are already used by other > callbacks on this call path, so we can't use cb->args[0] any > more, use cb->args[4] instead.
It's a common mechanism to save rhashtable iterator pointer in cb->args after tipc_dump_start() and tipc_dump_done() are introduced. Someday probably we will involve new dumpit function. In order to lower the risk that rhashtable iterator pointer saved is overwritten, it's better to use the last slot, ie, cb->args[5]. ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ tipc-discussion mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/tipc-discussion
