From: Daniel Borkmann <dan...@iogearbox.net> Date: Fri, 10 Jun 2016 23:10:22 +0200
> Add a possibility where the user can just specify the parent and > all filters under that parent are then being purged. Currently, > for example for scripting, one needs to specify pref/prio to have > a well-defined number for 'tc filter del' command for addressing > the previously created instance or additionally filter handle in > case of priorities being the same. Improve usage by allowing the > option for tc to specify the parent and removing the whole chain > for that given parent. > > Example usage after patch, no tc changes required: ... > Previously, RTM_DELTFILTER requests with invalid prio of 0 were > rejected, so only netlink requests with RTM_NEWTFILTER and NLM_F_CREATE > flag were allowed where the kernel would auto-generate a pref/prio. > We can piggyback on that and use prio of 0 as a wildcard for > requests of RTM_DELTFILTER. > > For notifying tc netlink monitoring users (e.g. libnl uses this > for caching), there are two options, that is, sending individual > tfilter_notify() notifications for each tcf_proto, or sending a > single one indicating wildcard removal. I tried both and there > are pros and cons for each, eventually I decided for sending > individual tfilter_notify(), so that user space can support this > seamlessly and there won't be a mess of changing each and every > application to make sure expectations from the kernel won't break > when they don't understand single notification. Since linear chains > don't really scale, I expect only a handful of classifiers to be > attached at max for a given parent anyway. > > Signed-off-by: Daniel Borkmann <dan...@iogearbox.net> > Acked-by: Jamal Hadi Salim <j...@mojatatu.com> Applied.
