Hi and sorry for late response,
> -----Original Message----- > From: Olivier Matz <olivier.m...@6wind.com> > Sent: Thursday, April 8, 2021 5:11 PM > To: Raslan Darawsheh <rasl...@nvidia.com> > Cc: dev@dpdk.org; ferruh.yi...@intel.com; Ori Kam <or...@nvidia.com>; > andrew.rybche...@oktetlabs.ru; ivan.ma...@oktetlabs.ru; > ying.a.w...@intel.com; Slava Ovsiienko <viachesl...@nvidia.com>; Shiri > Kuzin <shi...@nvidia.com> > Subject: Re: [PATCH v4 1/2] ethdev: add new ext hdr for gtp psc > > On Thu, Apr 08, 2021 at 12:37:27PM +0000, Raslan Darawsheh wrote: > > Hi Olivier, > > > > > -----Original Message----- > > > From: Olivier Matz <olivier.m...@6wind.com> > > > Sent: Thursday, April 8, 2021 3:30 PM > > > To: Raslan Darawsheh <rasl...@nvidia.com> > > > Cc: dev@dpdk.org; ferruh.yi...@intel.com; Ori Kam <or...@nvidia.com>; > > > andrew.rybche...@oktetlabs.ru; ivan.ma...@oktetlabs.ru; > > > ying.a.w...@intel.com; Slava Ovsiienko <viachesl...@nvidia.com>; Shiri > > > Kuzin <shi...@nvidia.com> > > > Subject: Re: [PATCH v4 1/2] ethdev: add new ext hdr for gtp psc > > > > > > Hi Raslan, > > > > > > On Sun, Apr 04, 2021 at 10:45:51AM +0300, Raslan Darawsheh wrote: > > > > Define new rte header for gtp PDU session container > > > > based on RFC 38415-g30 > > > > > > Do you have a link to this RFC? > > Yes sure, > > > https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fww > w.3gpp.org%2Fftp%2FSpecs%2Farchive%2F38_series%2F38.415%2F38415- > g30.zip&data=04%7C01%7Crasland%40nvidia.com%7C5279dde172024bc > d1f6b08d8fa981668%7C43083d15727340c1b7db39efd9ccc17a%7C0%7C0%7C6 > 37534878435191995%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMD > AiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata= > LuD7%2FvJgqJbZ78ncaM7UrpiLNPUt7zbPPfSMemyb2Y8%3D&reserved > =0 > > > > > > > > > Signed-off-by: Raslan Darawsheh <rasl...@nvidia.com> > > > > --- > > > > lib/librte_net/rte_gtp.h | 34 > ++++++++++++++++++++++++++++++++++ > > > > 1 file changed, 34 insertions(+) > > > > > > > > diff --git a/lib/librte_net/rte_gtp.h b/lib/librte_net/rte_gtp.h > > > > index 6a6f9b238d..088b0b5a53 100644 > > > > --- a/lib/librte_net/rte_gtp.h > > > > +++ b/lib/librte_net/rte_gtp.h > > > > @@ -61,6 +61,40 @@ struct rte_gtp_hdr_ext_word { > > > > uint8_t next_ext; /**< Next Extension Header Type. */ > > > > } __rte_packed; > > > > > > > > +/** > > > > + * Optional extension for GTP with next_ext set to 0x85 > > > > + * defined based on RFC 38415-g30. > > > > + */ > > > > +__extension__ > > > > +struct rte_gtp_psc_hdr { > > > > + uint8_t ext_hdr_len; /**< PDU ext hdr len in multiples of 4 > > > > bytes */ > > > > + uint8_t type:4; /**< PDU type */ > > > > + uint8_t qmp:1; /**< Qos Monitoring Packet */ > > > > + union { > > > > + struct { > > > > + uint8_t snp:1; /**< Sequence number presence */ > > > > + uint8_t spare_dl1:2; /**< spare down link bits > > > > */ > > > > + }; > > > > + struct { > > > > + uint8_t dl_delay_ind:1; /**< dl delay result > > > > presence > > > */ > > > > + uint8_t ul_delay_ind:1; /**< ul delay result > > > > presence > > > */ > > > > + uint8_t snp_ul1:1; /**< Sequence number presence > > > ul */ > > > > + }; > > > > + }; > > > > + union { > > > > + struct { > > > > + uint8_t ppp:1; /**< Paging policy presence */ > > > > + uint8_t rqi:1; /**< Reflective Qos Indicator */ > > > > + }; > > > > + struct { > > > > + uint8_t n_delay_ind:1; /**< N3/N9 delay result > > > presence */ > > > > + uint8_t spare_ul2:1; /**< spare up link bits */ > > > > + }; > > > > + }; > > > > + uint8_t qfi:6; /**< Qos Flow Identifier */ > > > > + uint8_t data[0]; /**< data feilds */ > > > > +} __rte_packed; > > > > > > With this header, sizeof(rte_gtp_psc_hdr) = 5, is it really expected? > > The data[0] is variable length data, I guess I should send another version > > to > mention that in the comment maybe. > > The header size according to the spec should be 4 octets aligned in general. > > What I wanted to highlight is that using union of structs containing > bitfields does not work as you expect: each union is at least 1 byte. > This results in a structure that does not match the expected header. I see thanks for explaining. > > > > > > > It would help to see the specification to have a better idea of how to > > Sure, I've just posted the link above, please let me know of any suggestion > that you have, and I'll be glad to do accordingly. > > > > > split, but a possible solution is to do something like this: > > > > > > struct rte_gtp_psc_generic_hdr { > > > uint8_t ext_hdr_len; > > > uint8_t type:4 > > > uint8_t qmp:1; > > > uint8_t pad:3; > > > }; > > > > > > struct rte_gtp_psc_<name1>_hdr { > > > uint8_t ext_hdr_len; > > > uint8_t type:4 > > > uint8_t qmp:1; > > > uint8_t uint8_t snp:1; > > > uint8_t spare_dl1:2; > > > ... > > > }; > > > > > > ... > > > > > > struct rte_gtp_psc_hdr { > > > union { > > > struct rte_gtp_psc_generic_hdr generic; > > > struct rte_gtp_psc_<name1>_hdr <name1>; > > > struct rte_gtp_psc_<name2>_hdr <name2>; > > > }; > > > }; > > From what I see in the documation, I think this approach should > work. From afar, I suggest: > > struct rte_gtp_psc_generic_hdr { > #if big endian > uint8_t type:4 > uint8_t qmp:1; > uint8_t pad:3; > #else > uint8_t pad:3; > uint8_t qmp:1; > uint8_t type:4 > #endif > }; > > struct rte_gtp_psc_type0_hdr { > #if big endian > uint8_t type:4 > uint8_t qmp:1; > uint8_t snp:1; > uint8_t spare:2; > > uint8_t ppp:1; > ... > #else > uint8_t pad:3; > uint8_t qmp:1; > uint8_t type:4 > uint8_t spare:2; > uint8_t snp:1; > > ... > #endif > uint8_t data[0]; /* for variable fields */ > }; > > struct rte_gtp_psc_type1_hdr { > ... same for fixed fields of type1 > > > uint8_t data[0]; /* for variable fields */ > }; > Sure, will consider and do it this way in the next version. > I don't see in the spec where is the reference to ext_hdr_len. > The ext_hdr_len is part of the definition for all ext_hdrs see this link for more details: https://en.wikipedia.org/wiki/GPRS_Tunnelling_Protocol So, it's not mentioned in the doc. > Regards, > Olivier
