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 * tl_retry_count, a number in the range 2..7 specifying the 65 IB RC retry count. 66 * queue_size, the maximum number of commands that the 67 initiator is allowed to queue per SCSI host. The default 68 value for this parameter is 62. The lowest supported value 69 is 2. 70 71What: /sys/class/infiniband_srp/srp-<hca>-<port_number>/ibdev 72Date: January 2, 2006 73KernelVersion: 2.6.15 74Contact: linux-rdma@vger.kernel.org 75Description: HCA name (<hca>). 76 77What: /sys/class/infiniband_srp/srp-<hca>-<port_number>/port 78Date: January 2, 2006 79KernelVersion: 2.6.15 80Contact: linux-rdma@vger.kernel.org 81Description: HCA port number (<port_number>). 82 83What: /sys/class/scsi_host/host<n>/allow_ext_sg 84Date: May 19, 2011 85KernelVersion: 2.6.39 86Contact: linux-rdma@vger.kernel.org 87Description: Whether ib_srp is allowed to include a partial memory 88 descriptor list in an SRP_CMD when communicating with an SRP 89 target. 90 91What: /sys/class/scsi_host/host<n>/cmd_sg_entries 92Date: May 19, 2011 93KernelVersion: 2.6.39 94Contact: linux-rdma@vger.kernel.org 95Description: Maximum number of data buffer descriptors that may be sent to 96 the target in a single SRP_CMD request. 97 98What: /sys/class/scsi_host/host<n>/dgid 99Date: June 17, 2006 100KernelVersion: 2.6.17 101Contact: linux-rdma@vger.kernel.org 102Description: InfiniBand destination GID used for communication with the SRP 103 target. Differs from orig_dgid if port redirection has happened. 104 105What: /sys/class/scsi_host/host<n>/id_ext 106Date: June 17, 2006 107KernelVersion: 2.6.17 108Contact: linux-rdma@vger.kernel.org 109Description: Eight-byte identifier extension portion of the 16-byte target 110 port identifier. 111 112What: /sys/class/scsi_host/host<n>/ioc_guid 113Date: June 17, 2006 114KernelVersion: 2.6.17 115Contact: linux-rdma@vger.kernel.org 116Description: Eight-byte I/O controller GUID portion of the 16-byte target 117 port identifier. 118 119What: /sys/class/scsi_host/host<n>/local_ib_device 120Date: November 29, 2006 121KernelVersion: 2.6.19 122Contact: linux-rdma@vger.kernel.org 123Description: Name of the InfiniBand HCA used for communicating with the 124 SRP target. 125 126What: /sys/class/scsi_host/host<n>/local_ib_port 127Date: November 29, 2006 128KernelVersion: 2.6.19 129Contact: linux-rdma@vger.kernel.org 130Description: Number of the HCA port used for communicating with the 131 SRP target. 132 133What: /sys/class/scsi_host/host<n>/orig_dgid 134Date: June 17, 2006 135KernelVersion: 2.6.17 136Contact: linux-rdma@vger.kernel.org 137Description: InfiniBand destination GID specified in the parameters 138 written to the add_target sysfs attribute. 139 140What: /sys/class/scsi_host/host<n>/pkey 141Date: June 17, 2006 142KernelVersion: 2.6.17 143Contact: linux-rdma@vger.kernel.org 144Description: A 16-bit number representing the InfiniBand partition key used 145 for communication with the SRP target. 146 147What: /sys/class/scsi_host/host<n>/req_lim 148Date: October 20, 2010 149KernelVersion: 2.6.36 150Contact: linux-rdma@vger.kernel.org 151Description: Number of requests ib_srp can send to the target before it has 152 to wait for more credits. For more information see also the 153 SRP credit algorithm in the SRP specification. 154 155What: /sys/class/scsi_host/host<n>/service_id 156Date: June 17, 2006 157KernelVersion: 2.6.17 158Contact: linux-rdma@vger.kernel.org 159Description: InfiniBand service ID used for establishing communication with 160 the SRP target. 161 162What: /sys/class/scsi_host/host<n>/sgid 163Date: February 1, 2014 164KernelVersion: 3.13 165Contact: linux-rdma@vger.kernel.org 166Description: InfiniBand GID of the source port used for communication with 167 the SRP target. 168 169What: /sys/class/scsi_host/host<n>/zero_req_lim 170Date: September 20, 2006 171KernelVersion: 2.6.18 172Contact: linux-rdma@vger.kernel.org 173Description: Number of times the initiator had to wait before sending a 174 request to the target because it ran out of credits. For more 175 information see also the SRP credit algorithm in the SRP 176 specification. 177