From mboxrd@z Thu Jan 1 00:00:00 1970 From: Or Gerlitz Subject: Re: [RFC PATCH 03/16] ib/mad: Add check for jumbo MADs support on a device Date: Thu, 8 Jan 2015 13:41:36 +0200 Message-ID: <54AE6CF0.30902@mellanox.com> References: <1415908465-24392-1-git-send-email-ira.weiny@intel.com> <1415908465-24392-4-git-send-email-ira.weiny@intel.com> <54770F44.2090909@mellanox.com> <54772C70.8060602@dev.mellanox.co.il> <54773C59.6080505@mellanox.com> <2807E5FD2F6FDA4886F6618EAC48510E0CBEE86E@CRSMSX101.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <2807E5FD2F6FDA4886F6618EAC48510E0CBEE86E-8k97q/ur5Z2krb+BlOpmy7fspsVTdybXVpNB7YpNyf8@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "Weiny, Ira" Cc: Sagi Grimberg , "roland-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: linux-rdma@vger.kernel.org On 1/7/2015 6:32 PM, Weiny, Ira wrote: >> >On 11/27/2014 3:51 PM, Sagi Grimberg wrote: >>> > >We're already short on bits in device_cap_flags >> > >> >no shortage @ the kernel... we can add more 32 bits if/when we need it > Why is there a gap in the bits? > > enum ib_device_cap_flags { > ... > IB_DEVICE_MEM_WINDOW_TYPE_2B = (1<<24), > IB_DEVICE_MANAGED_FLOW_STEERING = (1<<29), > ... > }; > > 25-28 are not used? Is there some legacy software out there which uses these? sort of... the verbs RSS design which wasn't accepted upstream uses bits 25/26/27 and Mellanox Core-Direct (whose verbs model called "Cross-Channel") which wasn't submitted upstream yet uses bit 28. Since in the kernel we can trivially use 64 bits, I would opt to keep these entries free for now. Or. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html