On 2013-06-13 18:28, Manuel Huber wrote: > Hello! > >> Xenomai only dispatches the IOCTL syscall to the driver's IOCTL handler. >> It does not interpret the request issued this way. What happens then can >> easily be traced by following the handler in RTnet: IOCTLs on UDP >> sockets, e.g., enter at rt_udp_ioctl. There you also find a use case of >> rt_socket_common_ioctl. > > Okay, I was a little confused, but I think I understood it now. > > I'm not sure if the current implementation is okay, I'm still a little > confused with the levels (SOL_IP, SOL_SOCKET) and their relation > and purpose... I have just moved the control of the timestamping > to ipv4's /ioctl/ call which checks the level and either calls > rt_ip_setsockopt > or rt_socket_setsockopt (same for ...getsockopt). > > I have also tried to fix my repository, but it's still not perfect I > fear. I > was amazed how powerfull rebase and add -p are ;) > Intermediate commits won't really work. Shall I fix this as well or > reduce some more commits? The current state can be viewed at > https://bitbucket.org/robinreal/rtnetts/overview tmp_rebase_2 branch. > > It's not finished yet, I plan to test everything once again on different > machines > but at least SCM_TIMESTAMPNS64 (the new timestamping mechanism) should > work. > >> But I think I have already figured out: it's on line 2166 and 2169 in >> __sys_recvmsg (net/socket.c). The socket level recvmsg functions >> operate on a copy in kernel space and the original user structure >> doesn't get modified (therefore the original address is still >> available in msg_control); the __put_user function just updates the >> msg_controllen field.
More precisely, msg_controllen and msg_flags are written back. I didn't find an explicit statement in the POSIX spec that says the other fields have to remain unchanged, but I guess there is code assuming this. > What do you think about the different handling of struct msghdr in > regular linux > and RTDM? I believe the cmsg part should get fixed in RTDM instead of > udp.c. > > RTAI 3.5 > Should there be a change in addons/rtdm/module.c the function > sys_rtdm_recvmsg in Line 116 > > Xenomai > Should there be a change in ksrc/skins/rtdm/syscall.c the function > sys_rtdm_recvmsg in Line 96 > > Or is it better (and less effort) to just pay attention to fix the cmsg > struct in udp_recvmsg as it's > currently done and maybe do that again if the feature should be > implemented for some other > protocol? I'm fine with changing the write-back logic at RTDM level. Send a patch, and I will ack it for Xenomai. Jan
signature.asc
Description: OpenPGP digital signature
------------------------------------------------------------------------------ This SF.net email is sponsored by Windows: Build for Windows Store. http://p.sf.net/sfu/windows-dev2dev
_______________________________________________ RTnet-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/rtnet-developers
