On (12/01/15 16:50), Maximilian Wilhelm wrote: > What I have in mind is that the user can supply a list of (ifname -> > ifindex) entries via a sysfs/procfs interface and if such a list is > present, the kernel will search the list for every ifname which is
Having the user supply such a list is hazardous for the reason below, esp if you consider that you can have virtual interfaces that take up that number. It also allows for a sparse ifindex number space, which can be inefficient (thus the cisco choice) > What I'm not sure about is what to do if there is any entry in the > list but the ifindex is already in use. One option would be to fail > the register call because the user wanted this particular ifindex .. If you want to do this, it's simpler to have the kernel track 2 separate indices (the packed index and the sparse snmp-index) per net_device. Changes to achieve it are non-trivial, of course, and that's why I'd question how badly this is needed. the other issue to confront is- what do you want ioctls like SIOCGIFINDEX to return- the packed one or the sparse one? What about if_nametoindex etc? If they return the sparse index, can they use it back with existing ifioctl and other calls? i.e., API compat will have some rough edges. --Sowmini -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html