From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leon Romanovsky Subject: [PATCH rdma-next 4/5] IB/core: Take into account optional UDR, XRC headers and mandatory ICRC for RoCE MTU Date: Mon, 16 Oct 2017 08:28:11 +0300 Message-ID: <20171016052812.28802-5-leon@kernel.org> References: <20171016052812.28802-1-leon@kernel.org> Return-path: In-Reply-To: <20171016052812.28802-1-leon-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Doug Ledford Cc: linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Leon Romanovsky , Parav Pandit List-Id: linux-rdma@vger.kernel.org From: Parav Pandit This fix considers optional UDP, XRC header sizes and mandatory ICRC 4 bytes in calculation of path MTU, by considering additional 8 bytes, path MTU calculation is more accurate. Link: https://www.spinics.net/lists/linux-rdma/msg54558.html Fixes: 3c86aa70bf67 ("RDMA/cm: Add RDMA CM support for IBoE devices") Signed-off-by: Parav Pandit Reviewed-by: Daniel Jurgens Reported-by: Roland Dreier Signed-off-by: Leon Romanovsky --- include/rdma/ib_addr.h | 7 ++++--- include/rdma/ib_pack.h | 19 +++++++++++-------- 2 files changed, 15 insertions(+), 11 deletions(-) diff --git a/include/rdma/ib_addr.h b/include/rdma/ib_addr.h index cfa82d16573d..b2a10c762304 100644 --- a/include/rdma/ib_addr.h +++ b/include/rdma/ib_addr.h @@ -245,10 +245,11 @@ static inline void rdma_addr_set_dgid(struct rdma_dev_addr *dev_addr, union ib_g static inline enum ib_mtu iboe_get_mtu(int mtu) { /* - * reduce IB headers from effective IBoE MTU. 28 stands for - * atomic header which is the biggest possible header after BTH + * Reduce IB headers from effective IBoE MTU. */ - mtu = mtu - IB_GRH_BYTES - IB_BTH_BYTES - 28; + mtu = mtu - (IB_GRH_BYTES + IB_UDP_BYTES + IB_BTH_BYTES + + IB_EXT_XRC_BYTES + IB_EXT_ATOMICETH_BYTES + + IB_ICRC_BYTES); if (mtu >= ib_mtu_enum_to_int(IB_MTU_4096)) return IB_MTU_4096; diff --git a/include/rdma/ib_pack.h b/include/rdma/ib_pack.h index 36655899ee02..7ea1382ad0e5 100644 --- a/include/rdma/ib_pack.h +++ b/include/rdma/ib_pack.h @@ -37,14 +37,17 @@ #include enum { - IB_LRH_BYTES = 8, - IB_ETH_BYTES = 14, - IB_VLAN_BYTES = 4, - IB_GRH_BYTES = 40, - IB_IP4_BYTES = 20, - IB_UDP_BYTES = 8, - IB_BTH_BYTES = 12, - IB_DETH_BYTES = 8 + IB_LRH_BYTES = 8, + IB_ETH_BYTES = 14, + IB_VLAN_BYTES = 4, + IB_GRH_BYTES = 40, + IB_IP4_BYTES = 20, + IB_UDP_BYTES = 8, + IB_BTH_BYTES = 12, + IB_DETH_BYTES = 8, + IB_EXT_ATOMICETH_BYTES = 28, + IB_EXT_XRC_BYTES = 4, + IB_ICRC_BYTES = 4 }; struct ib_field { -- 2.14.2 -- 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