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 10 * id_ext, a 16-digit hexadecimal number specifying the eight 11 byte identifier extension in the 16-byte SRP target port 12 identifier. The target port identifier is sent by ib_srp 13 to the target in the SRP_LOGIN_REQ request. 14 * ioc_guid, a 16-digit hexadecimal number specifying the eight 15 byte I/O controller GUID portion of the 16-byte target port 16 identifier. 17 * dgid, a 32-digit hexadecimal number specifying the 18 destination GID. 19 * pkey, a four-digit hexadecimal number specifying the 20 InfiniBand partition key. 21 * service_id, a 16-digit hexadecimal number specifying the 22 InfiniBand service ID used to establish communication with 23 the SRP target. How to find out the value of the service ID 24 is specified in the documentation of the SRP target. 25 * max_sect, a decimal number specifying the maximum number of 26 512-byte sectors to be transferred via a single SCSI command. 27 * max_cmd_per_lun, a decimal number specifying the maximum 28 number of outstanding commands for a single LUN. 29 * io_class, a hexadecimal number specifying the SRP I/O class. 30 Must be either 0xff00 (rev 10) or 0x0100 (rev 16a). The I/O 31 class defines the format of the SRP initiator and target 32 port identifiers. 33 * initiator_ext, a 16-digit hexadecimal number specifying the 34 identifier extension portion of the SRP initiator port 35 identifier. This data is sent by the initiator to the target 36 in the SRP_LOGIN_REQ request. 37 * cmd_sg_entries, a number in the range 1..255 that specifies 38 the maximum number of data buffer descriptors stored in the 39 SRP_CMD information unit itself. With allow_ext_sg=0 the 40 parameter cmd_sg_entries defines the maximum S/G list length 41 for a single SRP_CMD, and commands whose S/G list length 42 exceeds this limit after S/G list collapsing will fail. 43 * allow_ext_sg, whether ib_srp is allowed to include a partial 44 memory descriptor list in an SRP_CMD instead of the entire 45 list. If a partial memory descriptor list has been included 46 in an SRP_CMD the remaining memory descriptors are 47 communicated from initiator to target via an additional RDMA 48 transfer. Setting allow_ext_sg to 1 increases the maximum 49 amount of data that can be transferred between initiator and 50 target via a single SCSI command. Since not all SRP target 51 implementations support partial memory descriptor lists the 52 default value for this option is 0. 53 * sg_tablesize, a number in the range 1..2048 specifying the 54 maximum S/G list length the SCSI layer is allowed to pass to 55 ib_srp. Specifying a value that exceeds cmd_sg_entries is 56 only safe with partial memory descriptor list support enabled 57 (allow_ext_sg=1). 58 * comp_vector, a number in the range 0..n-1 specifying the 59 MSI-X completion vector of the first RDMA channel. Some 60 HCA's allocate multiple (n) MSI-X vectors per HCA port. If 61 the IRQ affinity masks of these interrupts have been 62 configured such that each MSI-X interrupt is handled by a 63 different CPU then the comp_vector parameter can be used to 64 spread the SRP completion workload over multiple CPU's. 65 * tl_retry_count, a number in the range 2..7 specifying the 66 IB RC retry count. 67 * queue_size, the maximum number of commands that the 68 initiator is allowed to queue per SCSI host. The default 69 value for this parameter is 62. The lowest supported value 70 is 2. 71 * max_it_iu_size, a decimal number specifying the maximum 72 initiator to target information unit length. 73 74What: /sys/class/infiniband_srp/srp-<hca>-<port_number>/ibdev 75Date: January 2, 2006 76KernelVersion: 2.6.15 77Contact: linux-rdma@vger.kernel.org 78Description: HCA name (<hca>). 79 80What: /sys/class/infiniband_srp/srp-<hca>-<port_number>/port 81Date: January 2, 2006 82KernelVersion: 2.6.15 83Contact: linux-rdma@vger.kernel.org 84Description: HCA port number (<port_number>). 85 86What: /sys/class/scsi_host/host<n>/allow_ext_sg 87Date: May 19, 2011 88KernelVersion: 2.6.39 89Contact: linux-rdma@vger.kernel.org 90Description: Whether ib_srp is allowed to include a partial memory 91 descriptor list in an SRP_CMD when communicating with an SRP 92 target. 93 94What: /sys/class/scsi_host/host<n>/ch_count 95Date: April 1, 2015 96KernelVersion: 3.19 97Contact: linux-rdma@vger.kernel.org 98Description: Number of RDMA channels used for communication with the SRP 99 target. 100 101What: /sys/class/scsi_host/host<n>/cmd_sg_entries 102Date: May 19, 2011 103KernelVersion: 2.6.39 104Contact: linux-rdma@vger.kernel.org 105Description: Maximum number of data buffer descriptors that may be sent to 106 the target in a single SRP_CMD request. 107 108What: /sys/class/scsi_host/host<n>/comp_vector 109Date: September 2, 2013 110KernelVersion: 3.11 111Contact: linux-rdma@vger.kernel.org 112Description: Completion vector used for the first RDMA channel. 113 114What: /sys/class/scsi_host/host<n>/dgid 115Date: June 17, 2006 116KernelVersion: 2.6.17 117Contact: linux-rdma@vger.kernel.org 118Description: InfiniBand destination GID used for communication with the SRP 119 target. Differs from orig_dgid if port redirection has happened. 120 121What: /sys/class/scsi_host/host<n>/id_ext 122Date: June 17, 2006 123KernelVersion: 2.6.17 124Contact: linux-rdma@vger.kernel.org 125Description: Eight-byte identifier extension portion of the 16-byte target 126 port identifier. 127 128What: /sys/class/scsi_host/host<n>/ioc_guid 129Date: June 17, 2006 130KernelVersion: 2.6.17 131Contact: linux-rdma@vger.kernel.org 132Description: Eight-byte I/O controller GUID portion of the 16-byte target 133 port identifier. 134 135What: /sys/class/scsi_host/host<n>/local_ib_device 136Date: November 29, 2006 137KernelVersion: 2.6.19 138Contact: linux-rdma@vger.kernel.org 139Description: Name of the InfiniBand HCA used for communicating with the 140 SRP target. 141 142What: /sys/class/scsi_host/host<n>/local_ib_port 143Date: November 29, 2006 144KernelVersion: 2.6.19 145Contact: linux-rdma@vger.kernel.org 146Description: Number of the HCA port used for communicating with the 147 SRP target. 148 149What: /sys/class/scsi_host/host<n>/orig_dgid 150Date: June 17, 2006 151KernelVersion: 2.6.17 152Contact: linux-rdma@vger.kernel.org 153Description: InfiniBand destination GID specified in the parameters 154 written to the add_target sysfs attribute. 155 156What: /sys/class/scsi_host/host<n>/pkey 157Date: June 17, 2006 158KernelVersion: 2.6.17 159Contact: linux-rdma@vger.kernel.org 160Description: A 16-bit number representing the InfiniBand partition key used 161 for communication with the SRP target. 162 163What: /sys/class/scsi_host/host<n>/req_lim 164Date: October 20, 2010 165KernelVersion: 2.6.36 166Contact: linux-rdma@vger.kernel.org 167Description: Number of requests ib_srp can send to the target before it has 168 to wait for more credits. For more information see also the 169 SRP credit algorithm in the SRP specification. 170 171What: /sys/class/scsi_host/host<n>/service_id 172Date: June 17, 2006 173KernelVersion: 2.6.17 174Contact: linux-rdma@vger.kernel.org 175Description: InfiniBand service ID used for establishing communication with 176 the SRP target. 177 178What: /sys/class/scsi_host/host<n>/sgid 179Date: February 1, 2014 180KernelVersion: 3.13 181Contact: linux-rdma@vger.kernel.org 182Description: InfiniBand GID of the source port used for communication with 183 the SRP target. 184 185What: /sys/class/scsi_host/host<n>/zero_req_lim 186Date: September 20, 2006 187KernelVersion: 2.6.18 188Contact: linux-rdma@vger.kernel.org 189Description: Number of times the initiator had to wait before sending a 190 request to the target because it ran out of credits. For more 191 information see also the SRP credit algorithm in the SRP 192 specification. 193