On 04/05/2018 03:47 AM, Jose Abreu wrote: > Hi All, > > I would like to know your opinion regarding adding support for > driver private ioctl's in ethtool. > > Background: Synopsys Ethernet IP's have a certain number of > features which can be reconfigured at runtime. Giving you two > examples: One of the most recent one is the safety features, > which can be enabled/disabled and forced at runtime. Another one > is a Flexible RX Parser which can route specific packets to > specific RX DMA channels. Given that these are features specific > to our IP's it would not be useful to add an uniform API for this > because the users would only be one or two drivers ...
Parsing of packets and directing the matched packets to specific queues/channels can be done through ethtool rxnfc API, tc/cls_flower as well, so you should really check whether those APIs don't already allow you to do what you want. ethtool already supports a concept of private flags, not ioctl() though which allows you to toggle boolean values for instance (or technically up to how many bits a "flag" is used to represent) is that enough or do you need to turn on/off the feature as well as pass configuration parameters? > > This new feature would change the help usage for ethtool so that > each driver private option would be shown, and then each driver > specific file would have a structure with all the available > options. Finally, each driver would have to handle the private > IOCTL's. > > We already have this working locally and now I would like to know > your opinion about upstreaming this ... Do you think this can be > useful for anyone else? Or should we change direction to use, for > example, debugfs/configfs? In general, even if there is only one driver implementing a particular feature, the approach chosen is to come up with an API that is as generic as possible. Even if there is a single user of that API in tree, having something that was thought to be generic is better than allowing uncontrolled private ioctl() implementations. -- Florian
