1What: /sys/class/infiniband_srp/srp-<hca>-<port_number>/add_target 2Date: January 2, 2006 3KernelVersion: 2.6.15 4Contact: linux-rdma@vger.kernel.org 5Description: Interface for making ib_srp connect to a new target. 6 One can request ib_srp to connect to a new target by writing 7 a comma-separated list of login parameters to this sysfs 8 attribute. The supported parameters are: 9 * id_ext, a 16-digit hexadecimal number specifying the eight 10 byte identifier extension in the 16-byte SRP target port 11 identifier. The target port identifier is sent by ib_srp 12 to the target in the SRP_LOGIN_REQ request. 13 * ioc_guid, a 16-digit hexadecimal number specifying the eight 14 byte I/O controller GUID portion of the 16-byte target port 15 identifier. 16 * dgid, a 32-digit hexadecimal number specifying the 17 destination GID. 18 * pkey, a four-digit hexadecimal number specifying the 19 InfiniBand partition key. 20 * service_id, a 16-digit hexadecimal number specifying the 21 InfiniBand service ID used to establish communication with 22 the SRP target. How to find out the value of the service ID 23 is specified in the documentation of the SRP target. 24 * max_sect, a decimal number specifying the maximum number of 25 512-byte sectors to be transferred via a single SCSI command. 26 * max_cmd_per_lun, a decimal number specifying the maximum 27 number of outstanding commands for a single LUN. 28 * io_class, a hexadecimal number specifying the SRP I/O class. 29 Must be either 0xff00 (rev 10) or 0x0100 (rev 16a). The I/O 30 class defines the format of the SRP initiator and target 31 port identifiers. 32 * initiator_ext, a 16-digit hexadecimal number specifying the 33 identifier extension portion of the SRP initiator port 34 identifier. This data is sent by the initiator to the target 35 in the SRP_LOGIN_REQ request. 36 * cmd_sg_entries, a number in the range 1..255 that specifies 37 the maximum number of data buffer descriptors stored in the 38 SRP_CMD information unit itself. With allow_ext_sg=0 the 39 parameter cmd_sg_entries defines the maximum S/G list length 40 for a single SRP_CMD, and commands whose S/G list length 41 exceeds this limit after S/G list collapsing will fail. 42 * allow_ext_sg, whether ib_srp is allowed to include a partial 43 memory descriptor list in an SRP_CMD instead of the entire 44 list. If a partial memory descriptor list has been included 45 in an SRP_CMD the remaining memory descriptors are 46 communicated from initiator to target via an additional RDMA 47 transfer. Setting allow_ext_sg to 1 increases the maximum 48 amount of data that can be transferred between initiator and 49 target via a single SCSI command. Since not all SRP target 50 implementations support partial memory descriptor lists the 51 default value for this option is 0. 52 * sg_tablesize, a number in the range 1..2048 specifying the 53 maximum S/G list length the SCSI layer is allowed to pass to 54 ib_srp. Specifying a value that exceeds cmd_sg_entries is 55 only safe with partial memory descriptor list support enabled 56 (allow_ext_sg=1). 57 * comp_vector, a number in the range 0..n-1 specifying the 58 MSI-X completion vector. Some HCA's allocate multiple (n) 59 MSI-X vectors per HCA port. If the IRQ affinity masks of 60 these interrupts have been configured such that each MSI-X 61 interrupt is handled by a different CPU then the comp_vector 62 parameter can be used to spread the SRP completion workload 63 over multiple CPU's. 64 65What: /sys/class/infiniband_srp/srp-<hca>-<port_number>/ibdev 66Date: January 2, 2006 67KernelVersion: 2.6.15 68Contact: linux-rdma@vger.kernel.org 69Description: HCA name (<hca>). 70 71What: /sys/class/infiniband_srp/srp-<hca>-<port_number>/port 72Date: January 2, 2006 73KernelVersion: 2.6.15 74Contact: linux-rdma@vger.kernel.org 75Description: HCA port number (<port_number>). 76 77What: /sys/class/scsi_host/host<n>/allow_ext_sg 78Date: May 19, 2011 79KernelVersion: 2.6.39 80Contact: linux-rdma@vger.kernel.org 81Description: Whether ib_srp is allowed to include a partial memory 82 descriptor list in an SRP_CMD when communicating with an SRP 83 target. 84 85What: /sys/class/scsi_host/host<n>/cmd_sg_entries 86Date: May 19, 2011 87KernelVersion: 2.6.39 88Contact: linux-rdma@vger.kernel.org 89Description: Maximum number of data buffer descriptors that may be sent to 90 the target in a single SRP_CMD request. 91 92What: /sys/class/scsi_host/host<n>/dgid 93Date: June 17, 2006 94KernelVersion: 2.6.17 95Contact: linux-rdma@vger.kernel.org 96Description: InfiniBand destination GID used for communication with the SRP 97 target. Differs from orig_dgid if port redirection has happened. 98 99What: /sys/class/scsi_host/host<n>/id_ext 100Date: June 17, 2006 101KernelVersion: 2.6.17 102Contact: linux-rdma@vger.kernel.org 103Description: Eight-byte identifier extension portion of the 16-byte target 104 port identifier. 105 106What: /sys/class/scsi_host/host<n>/ioc_guid 107Date: June 17, 2006 108KernelVersion: 2.6.17 109Contact: linux-rdma@vger.kernel.org 110Description: Eight-byte I/O controller GUID portion of the 16-byte target 111 port identifier. 112 113What: /sys/class/scsi_host/host<n>/local_ib_device 114Date: November 29, 2006 115KernelVersion: 2.6.19 116Contact: linux-rdma@vger.kernel.org 117Description: Name of the InfiniBand HCA used for communicating with the 118 SRP target. 119 120What: /sys/class/scsi_host/host<n>/local_ib_port 121Date: November 29, 2006 122KernelVersion: 2.6.19 123Contact: linux-rdma@vger.kernel.org 124Description: Number of the HCA port used for communicating with the 125 SRP target. 126 127What: /sys/class/scsi_host/host<n>/orig_dgid 128Date: June 17, 2006 129KernelVersion: 2.6.17 130Contact: linux-rdma@vger.kernel.org 131Description: InfiniBand destination GID specified in the parameters 132 written to the add_target sysfs attribute. 133 134What: /sys/class/scsi_host/host<n>/pkey 135Date: June 17, 2006 136KernelVersion: 2.6.17 137Contact: linux-rdma@vger.kernel.org 138Description: A 16-bit number representing the InfiniBand partition key used 139 for communication with the SRP target. 140 141What: /sys/class/scsi_host/host<n>/req_lim 142Date: October 20, 2010 143KernelVersion: 2.6.36 144Contact: linux-rdma@vger.kernel.org 145Description: Number of requests ib_srp can send to the target before it has 146 to wait for more credits. For more information see also the 147 SRP credit algorithm in the SRP specification. 148 149What: /sys/class/scsi_host/host<n>/service_id 150Date: June 17, 2006 151KernelVersion: 2.6.17 152Contact: linux-rdma@vger.kernel.org 153Description: InfiniBand service ID used for establishing communication with 154 the SRP target. 155 156What: /sys/class/scsi_host/host<n>/zero_req_lim 157Date: September 20, 2006 158KernelVersion: 2.6.18 159Contact: linux-rdma@vger.kernel.org 160Description: Number of times the initiator had to wait before sending a 161 request to the target because it ran out of credits. For more 162 information see also the SRP credit algorithm in the SRP 163 specification. 164