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 of the first RDMA channel. Some 59 HCA's allocate multiple (n) MSI-X vectors per HCA port. If 60 the IRQ affinity masks of these interrupts have been 61 configured such that each MSI-X interrupt is handled by a 62 different CPU then the comp_vector parameter can be used to 63 spread the SRP completion workload 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 * max_it_iu_size, a decimal number specifying the maximum 71 initiator to target information unit length. 72 73What: /sys/class/infiniband_srp/srp-<hca>-<port_number>/ibdev 74Date: January 2, 2006 75KernelVersion: 2.6.15 76Contact: linux-rdma@vger.kernel.org 77Description: HCA name (<hca>). 78 79What: /sys/class/infiniband_srp/srp-<hca>-<port_number>/port 80Date: January 2, 2006 81KernelVersion: 2.6.15 82Contact: linux-rdma@vger.kernel.org 83Description: HCA port number (<port_number>). 84 85What: /sys/class/scsi_host/host<n>/allow_ext_sg 86Date: May 19, 2011 87KernelVersion: 2.6.39 88Contact: linux-rdma@vger.kernel.org 89Description: Whether ib_srp is allowed to include a partial memory 90 descriptor list in an SRP_CMD when communicating with an SRP 91 target. 92 93What: /sys/class/scsi_host/host<n>/ch_count 94Date: April 1, 2015 95KernelVersion: 3.19 96Contact: linux-rdma@vger.kernel.org 97Description: Number of RDMA channels used for communication with the SRP 98 target. 99 100What: /sys/class/scsi_host/host<n>/cmd_sg_entries 101Date: May 19, 2011 102KernelVersion: 2.6.39 103Contact: linux-rdma@vger.kernel.org 104Description: Maximum number of data buffer descriptors that may be sent to 105 the target in a single SRP_CMD request. 106 107What: /sys/class/scsi_host/host<n>/comp_vector 108Date: September 2, 2013 109KernelVersion: 3.11 110Contact: linux-rdma@vger.kernel.org 111Description: Completion vector used for the first RDMA channel. 112 113What: /sys/class/scsi_host/host<n>/dgid 114Date: June 17, 2006 115KernelVersion: 2.6.17 116Contact: linux-rdma@vger.kernel.org 117Description: InfiniBand destination GID used for communication with the SRP 118 target. Differs from orig_dgid if port redirection has happened. 119 120What: /sys/class/scsi_host/host<n>/id_ext 121Date: June 17, 2006 122KernelVersion: 2.6.17 123Contact: linux-rdma@vger.kernel.org 124Description: Eight-byte identifier extension portion of the 16-byte target 125 port identifier. 126 127What: /sys/class/scsi_host/host<n>/ioc_guid 128Date: June 17, 2006 129KernelVersion: 2.6.17 130Contact: linux-rdma@vger.kernel.org 131Description: Eight-byte I/O controller GUID portion of the 16-byte target 132 port identifier. 133 134What: /sys/class/scsi_host/host<n>/local_ib_device 135Date: November 29, 2006 136KernelVersion: 2.6.19 137Contact: linux-rdma@vger.kernel.org 138Description: Name of the InfiniBand HCA used for communicating with the 139 SRP target. 140 141What: /sys/class/scsi_host/host<n>/local_ib_port 142Date: November 29, 2006 143KernelVersion: 2.6.19 144Contact: linux-rdma@vger.kernel.org 145Description: Number of the HCA port used for communicating with the 146 SRP target. 147 148What: /sys/class/scsi_host/host<n>/orig_dgid 149Date: June 17, 2006 150KernelVersion: 2.6.17 151Contact: linux-rdma@vger.kernel.org 152Description: InfiniBand destination GID specified in the parameters 153 written to the add_target sysfs attribute. 154 155What: /sys/class/scsi_host/host<n>/pkey 156Date: June 17, 2006 157KernelVersion: 2.6.17 158Contact: linux-rdma@vger.kernel.org 159Description: A 16-bit number representing the InfiniBand partition key used 160 for communication with the SRP target. 161 162What: /sys/class/scsi_host/host<n>/req_lim 163Date: October 20, 2010 164KernelVersion: 2.6.36 165Contact: linux-rdma@vger.kernel.org 166Description: Number of requests ib_srp can send to the target before it has 167 to wait for more credits. For more information see also the 168 SRP credit algorithm in the SRP specification. 169 170What: /sys/class/scsi_host/host<n>/service_id 171Date: June 17, 2006 172KernelVersion: 2.6.17 173Contact: linux-rdma@vger.kernel.org 174Description: InfiniBand service ID used for establishing communication with 175 the SRP target. 176 177What: /sys/class/scsi_host/host<n>/sgid 178Date: February 1, 2014 179KernelVersion: 3.13 180Contact: linux-rdma@vger.kernel.org 181Description: InfiniBand GID of the source port used for communication with 182 the SRP target. 183 184What: /sys/class/scsi_host/host<n>/zero_req_lim 185Date: September 20, 2006 186KernelVersion: 2.6.18 187Contact: linux-rdma@vger.kernel.org 188Description: Number of times the initiator had to wait before sending a 189 request to the target because it ran out of credits. For more 190 information see also the SRP credit algorithm in the SRP 191 specification. 192