On Mon, May 18, 2015 at 11:41 AM, Michael Wang <yun.wang@xxxxxxxxxxxxxxxx> wrote: > Since v1: > * Merge the descriptions from Doug: > http://www.spinics.net/lists/linux-rdma/msg25172.html > > This is the following patch for: > https://lkml.org/lkml/2015/5/5/417 > which try to document the settled rdma_cap_XX(). > > Highlights: > There could be many missing/mistakes/misunderstanding, please don't > be hesitate to point out the issues, any suggestions to improve or > complete the description are very welcomed ;-) Michael, none of what you wrote above belongs to the change-log which is going to stay for-ever in the upstream git repo. You should put it all belong the --- line after your S.O.B and add proper change log telling what this patch is about > > Signed-off-by: Michael Wang <yun.wang@xxxxxxxxxxxxxxxx> > --- > Documentation/infiniband/rdma_helpers.txt | 79 +++++++++++++++++++++++++++++++ > 1 file changed, 79 insertions(+) > create mode 100644 Documentation/infiniband/rdma_helpers.txt > > diff --git a/Documentation/infiniband/rdma_helpers.txt b/Documentation/infiniband/rdma_helpers.txt > new file mode 100644 > index 0000000..be9416d > --- /dev/null > +++ b/Documentation/infiniband/rdma_helpers.txt > @@ -0,0 +1,79 @@ > +RDMA HELPERS > + > + The following helpers are used to check the specific capabilities of a > + particular port before utilizing those capabilities. > + > + rdma_cap_ib_mad - Infiniband Management Datagrams. > + rdma_cap_ib_smi - Infiniband Subnet Management Interface. > + rdma_cap_ib_cm - Infiniband Communication Manager. > + rdma_cap_iw_cm - IWARP Communication Manager. > + rdma_cap_ib_sa - Infiniband Subnet Administration. > + rdma_cap_ib_mcast - Infiniband Multicast Join/Leave Protocol. > + rdma_cap_read_multi_sge - RDMA Read Work Request Support Multiple SGE. > + rdma_cap_af_ib - Native Infiniband Address. > + rdma_cap_eth_ah - InfiniBand Transport With Ethernet Address. > + > +USAGE > + > + if (rdma_cap_XX(device, i)) { > + /* The port i of device support XX */ > + ... > + } else { > + /* The port i of device don't support XX */ > + ... > + } > + > + rdma_cap_ib_mad > + --------------- > + Management Datagrams (MAD) are a required part of the InfiniBand > + specification and are supported on all InfiniBand devices. A slightly > + extended version are also supported on OPA interfaces. > + > + rdma_cap_ib_smi > + --------------- > + Subnet Management Interface (SMI) will handle SMP packet from SM > + in an infiniband fabric. > + > + rdma_cap_ib_cm > + --------------- > + Communication Manager (CM) service, used to ease the process of connecting > + to a remote host. The IB-CM can be used to connect to remote hosts using > + either InfiniBand or RoCE connections, iWARP has its own CM. > + > + rdma_cap_iw_cm > + --------------- > + iWARP Communication Manager (CM), Similar to the IB-CM, but only used on > + iWARP devices. > + > + rdma_cap_ib_sa > + --------------- > + Subnet Administration (SA) is the database built by SM in an > + infiniband fabric. > + > + rdma_cap_ib_mcast > + --------------- > + InfiniBand (and OPA) use a different multicast mechanism rather than > + traditional IP multicast found on Ethernet devices. If this is true, then > + traditional IPv4/IPv6 multicast is handled by the IPoIB layer and direct > + multicast joins and leaves are handled per the InfiniBand specifications. > + > + rdma_cap_read_multi_sge > + --------------- > + Certain devices (iWARP in particular) have restrictions on the number of > + scatter gather elements that can be present in an RDMA READ work request, > + this is true if the device does not have that restriction. > + > + rdma_cap_af_ib > + --------------- > + Many code paths for traditional InfiniBand and RoCE links are the same, > + but need minor differences to accommodate the different addresses on the > + two types of connections. This helper is true when the address of the > + specific connection is of the InfiniBand native variety. > + > + rdma_cap_eth_ah > + --------------- > + Queue Pair is InfiniBand transport, but uses Ethernet address instead > + of native InfiniBand address (aka, this is a RoCE QP, and that means > + ethertype 0x8915 + GRH for RoCEv1 and IP/UDP to well known UDP port for > + RoCEv2), this is true when the address family of the specific queue pair > + is of the Ethernet (RoCE) variety. > -- > 2.1.0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
