xref: /linux/Documentation/ABI/stable/sysfs-driver-ib_srp (revision a2cce7a9f1b8cc3d4edce106fb971529f1d4d9ce)
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
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>/ch_count
92Date:		April 1, 2015
93KernelVersion:	3.19
94Contact:	linux-rdma@vger.kernel.org
95Description:	Number of RDMA channels used for communication with the SRP
96		target.
97
98What:		/sys/class/scsi_host/host<n>/cmd_sg_entries
99Date:		May 19, 2011
100KernelVersion:	2.6.39
101Contact:	linux-rdma@vger.kernel.org
102Description:	Maximum number of data buffer descriptors that may be sent to
103		the target in a single SRP_CMD request.
104
105What:		/sys/class/scsi_host/host<n>/comp_vector
106Date:		September 2, 2013
107KernelVersion:	3.11
108Contact:	linux-rdma@vger.kernel.org
109Description:	Completion vector used for the first RDMA channel.
110
111What:		/sys/class/scsi_host/host<n>/dgid
112Date:		June 17, 2006
113KernelVersion:	2.6.17
114Contact:	linux-rdma@vger.kernel.org
115Description:	InfiniBand destination GID used for communication with the SRP
116		target. Differs from orig_dgid if port redirection has happened.
117
118What:		/sys/class/scsi_host/host<n>/id_ext
119Date:		June 17, 2006
120KernelVersion:	2.6.17
121Contact:	linux-rdma@vger.kernel.org
122Description:	Eight-byte identifier extension portion of the 16-byte target
123		port identifier.
124
125What:		/sys/class/scsi_host/host<n>/ioc_guid
126Date:		June 17, 2006
127KernelVersion:	2.6.17
128Contact:	linux-rdma@vger.kernel.org
129Description:	Eight-byte I/O controller GUID portion of the 16-byte target
130		port identifier.
131
132What:		/sys/class/scsi_host/host<n>/local_ib_device
133Date:		November 29, 2006
134KernelVersion:	2.6.19
135Contact:	linux-rdma@vger.kernel.org
136Description:	Name of the InfiniBand HCA used for communicating with the
137		SRP target.
138
139What:		/sys/class/scsi_host/host<n>/local_ib_port
140Date:		November 29, 2006
141KernelVersion:	2.6.19
142Contact:	linux-rdma@vger.kernel.org
143Description:	Number of the HCA port used for communicating with the
144		SRP target.
145
146What:		/sys/class/scsi_host/host<n>/orig_dgid
147Date:		June 17, 2006
148KernelVersion:	2.6.17
149Contact:	linux-rdma@vger.kernel.org
150Description:	InfiniBand destination GID specified in the parameters
151		written to the add_target sysfs attribute.
152
153What:		/sys/class/scsi_host/host<n>/pkey
154Date:		June 17, 2006
155KernelVersion:	2.6.17
156Contact:	linux-rdma@vger.kernel.org
157Description:	A 16-bit number representing the InfiniBand partition key used
158		for communication with the SRP target.
159
160What:		/sys/class/scsi_host/host<n>/req_lim
161Date:		October 20, 2010
162KernelVersion:	2.6.36
163Contact:	linux-rdma@vger.kernel.org
164Description:	Number of requests ib_srp can send to the target before it has
165		to wait for more credits. For more information see also the
166		SRP credit algorithm in the SRP specification.
167
168What:		/sys/class/scsi_host/host<n>/service_id
169Date:		June 17, 2006
170KernelVersion:	2.6.17
171Contact:	linux-rdma@vger.kernel.org
172Description:	InfiniBand service ID used for establishing communication with
173		the SRP	target.
174
175What:		/sys/class/scsi_host/host<n>/sgid
176Date:		February 1, 2014
177KernelVersion:	3.13
178Contact:	linux-rdma@vger.kernel.org
179Description:	InfiniBand GID of the source port used for communication with
180		the SRP target.
181
182What:		/sys/class/scsi_host/host<n>/zero_req_lim
183Date:		September 20, 2006
184KernelVersion:	2.6.18
185Contact:	linux-rdma@vger.kernel.org
186Description:	Number of times the initiator had to wait before sending a
187		request to the target because it ran out of credits. For more
188		information see also the SRP credit algorithm in the SRP
189		specification.
190