On Thu, 2011-12-01 at 20:09 +0100, Bart Van Assche wrote: > Document the ib_srp sysfs attributes according to the rules specified > in Documentation/ABI/README.
%s/ib_srp/SRP initiator/g > +What: > /sys/class/infiniband_srp/srp-<hca>-<port_number>/add_target > +Date: January 2, 2006 > +KernelVersion: 2.6.15 > +Contact: [email protected] > +Description: Interface for making ib_srp connect to a new target. > + One can request ib_srp to connect to a new target by writing > + a comma-separated list of login parameters to this sysfs > + attribute. The supported parameters are: > + * id_ext, a 16-digit hexadecimal number specifying the last > + eight bytes of the 16-byte target port identifier sent by > + ib_srp to the target in the SRP_LOGIN_REQ request. ... specifying the eight byte identifier extension portion of the SCSI target port identifier. First 8 or last 8 depends on io_class... > + * ioc_guid, a 16-digit hexadecimal number specifying the first > + eight bytes of the 16-byte target port identifier sent by > + ib_srp to the target in the SRP_LOGIN_REQ request. ... specifying the eight byte IOController GUID portion of the SCSI target port identifier. > + * dgid, a 16-digit hexadecimal number specifying the > + destination GID. > + * pkey, a four-digit hexadecimal number specifying the > + InfiniBand partition key. > + * service_id, a 16-digit hexadecimal number specifying the > + InfiniBand service ID used for communication with the SRP > + target. ... used to establish communication with the SRP target. > + * max_sect, a decimal number specifying the maximum number of > + sectors to be transferred via a single SRP_CMD request. 512 byte sectors, via a single SCSI command. > + * max_cmd_per_lun, a decimal number specifying the maximum > + number of outstanding commands per LUN. for a given LUN > + * io_class, a hexadecimal number specifying the SRP I/O class. > + Must be either 0xff00 (rev 10) or 0x0100 (rev 16a). > + * initiator_ext, a 16-digit hexadecimal number specifying the > + last eight bytes of the 16-byte initiator port identifier > + sent by ib_srp to the target in the SRP_LOGIN_REQ request. ... specifying the identifier extension portion of the SCSI initiator port ID. > + * cmd_sg_entries, the maximum number of memory descriptors > + that fit in a single SRP command when using the direct data > + buffer descriptor format. s/direct/indirect/ > + * allow_ext_sg, whether ib_srp is allowed to send SRP_CMD > + requests to the target with an indirect data buffer > + descriptor, that is a data buffer descriptor that has to be > + obtained by the target via an additional RDMA transfer. allow_ext_sg, set to non-zero to allow the initiator to send an indirect data buffer descriptor with more than cmd_sg_entries; portions of this descriptor must be obtained by the target via an additional RDMA transfer. The default is to never send such a request, as the SRP target must support this mode of operation. > + * sg_tablesize, a number specifying the maximum length of > + scatter/gather lists passed by the SCSI layer to ib_srp. ... maximum length of the scatter/gather lists supported by the SRP initiator. This value may be larger than cmd_sg_entries if allow_ext_sg is true, or the administrator accepts the (small) risk that fast memory registration will not be able to collapse the SG list into few enough entries. > + > +What: /sys/class/scsi_host/host<n>/allow_ext_sg > +Date: May 19, 2011 > +KernelVersion: 2.6.39 > +Contact: [email protected] > +Description: Whether ib_srp is allowed to send SRP_CMD requests to the > + target with an indirect data buffer descriptor, that is a > + data buffer descriptor that has to be obtained by the target > + via an additional RDMA transfer. If set to zero, ib_srp will > + refuse to process data transfers whose scatter/gather list > + length exceeds cmd_sg_entries. If true, the initiator believes the target will accept an indirect data buffer descriptor with more than cmd_sg_entries, which requires an additional RDMA operation. If false and memory registration mechanism fails to collapse the SG list to few enough entries, the initiator will fail the command. > + > +What: /sys/class/scsi_host/host<n>/cmd_sg_entries > +Date: May 19, 2011 > +KernelVersion: 2.6.39 > +Contact: [email protected] > +Description: See also allow_ext_sg. Maximum number of indirect data buffer descriptors that will fit inside the request buffer without requiring an additional RDMA operation. > +What: /sys/class/scsi_host/host<n>/id_ext > +What: /sys/class/scsi_host/host<n>/ioc_guid Same comments as for add_target. > +What: /sys/class/scsi_host/host<n>/service_id > +Date: June 17, 2006 > +KernelVersion: 2.6.17 > +Contact: [email protected] > +Description: InfiniBand service ID used for communication with the SRP > + target. ... for the InfiniBand connection management request used to establish communication with the SRP target. Interesting that we don't seem to have a sysfs entry for the initiator ID value used. -- Dave Dillow National Center for Computational Science Oak Ridge National Laboratory (865) 241-6602 office -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
