1/* 2 * Copyright (c) 2006 - 2009 Mellanox Technology Inc. All rights reserved. 3 * Copyright (C) 2009 - 2010 Bart Van Assche <bvanassche@acm.org>. 4 * 5 * This software is available to you under a choice of one of two 6 * licenses. You may choose to be licensed under the terms of the GNU 7 * General Public License (GPL) Version 2, available from the file 8 * COPYING in the main directory of this source tree, or the 9 * OpenIB.org BSD license below: 10 * 11 * Redistribution and use in source and binary forms, with or 12 * without modification, are permitted provided that the following 13 * conditions are met: 14 * 15 * - Redistributions of source code must retain the above 16 * copyright notice, this list of conditions and the following 17 * disclaimer. 18 * 19 * - Redistributions in binary form must reproduce the above 20 * copyright notice, this list of conditions and the following 21 * disclaimer in the documentation and/or other materials 22 * provided with the distribution. 23 * 24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 31 * SOFTWARE. 32 * 33 */ 34 35#ifndef IB_SRPT_H 36#define IB_SRPT_H 37 38#include <linux/types.h> 39#include <linux/list.h> 40#include <linux/wait.h> 41 42#include <rdma/ib_verbs.h> 43#include <rdma/ib_sa.h> 44#include <rdma/ib_cm.h> 45#include <rdma/rdma_cm.h> 46#include <rdma/rw.h> 47 48#include <scsi/srp.h> 49 50#include "ib_dm_mad.h" 51 52/* 53 * The prefix the ServiceName field must start with in the device management 54 * ServiceEntries attribute pair. See also the SRP specification. 55 */ 56#define SRP_SERVICE_NAME_PREFIX "SRP.T10:" 57 58struct srpt_nexus; 59 60enum { 61 /* 62 * SRP IOControllerProfile attributes for SRP target ports that have 63 * not been defined in <scsi/srp.h>. Source: section B.7, table B.7 64 * in the SRP specification. 65 */ 66 SRP_PROTOCOL = 0x0108, 67 SRP_PROTOCOL_VERSION = 0x0001, 68 SRP_IO_SUBCLASS = 0x609e, 69 SRP_SEND_TO_IOC = 0x01, 70 SRP_SEND_FROM_IOC = 0x02, 71 SRP_RDMA_READ_FROM_IOC = 0x08, 72 SRP_RDMA_WRITE_FROM_IOC = 0x20, 73 74 /* 75 * srp_login_cmd.req_flags bitmasks. See also table 9 in the SRP 76 * specification. 77 */ 78 SRP_MTCH_ACTION = 0x03, /* MULTI-CHANNEL ACTION */ 79 SRP_LOSOLNT = 0x10, /* logout solicited notification */ 80 SRP_CRSOLNT = 0x20, /* credit request solicited notification */ 81 SRP_AESOLNT = 0x40, /* asynchronous event solicited notification */ 82 83 /* 84 * srp_cmd.sol_nt / srp_tsk_mgmt.sol_not bitmasks. See also tables 85 * 18 and 20 in the SRP specification. 86 */ 87 SRP_SCSOLNT = 0x02, /* SCSOLNT = successful solicited notification */ 88 SRP_UCSOLNT = 0x04, /* UCSOLNT = unsuccessful solicited notification */ 89 90 /* 91 * srp_rsp.sol_not / srp_t_logout.sol_not bitmasks. See also tables 92 * 16 and 22 in the SRP specification. 93 */ 94 SRP_SOLNT = 0x01, /* SOLNT = solicited notification */ 95 96 /* See also table 24 in the SRP specification. */ 97 SRP_TSK_MGMT_SUCCESS = 0x00, 98 SRP_TSK_MGMT_FUNC_NOT_SUPP = 0x04, 99 SRP_TSK_MGMT_FAILED = 0x05, 100 101 /* See also table 21 in the SRP specification. */ 102 SRP_CMD_SIMPLE_Q = 0x0, 103 SRP_CMD_HEAD_OF_Q = 0x1, 104 SRP_CMD_ORDERED_Q = 0x2, 105 SRP_CMD_ACA = 0x4, 106 107 SRPT_DEF_SG_TABLESIZE = 128, 108 109 MIN_SRPT_SQ_SIZE = 16, 110 DEF_SRPT_SQ_SIZE = 4096, 111 MAX_SRPT_RQ_SIZE = 128, 112 MIN_SRPT_SRQ_SIZE = 4, 113 DEFAULT_SRPT_SRQ_SIZE = 4095, 114 MAX_SRPT_SRQ_SIZE = 65535, 115 MAX_SRPT_RDMA_SIZE = 1U << 24, 116 MAX_SRPT_RSP_SIZE = 1024, 117 118 SRP_MAX_ADD_CDB_LEN = 16, 119 SRP_MAX_IMM_DATA_OFFSET = 80, 120 SRP_MAX_IMM_DATA = 8 * 1024, 121 MIN_MAX_REQ_SIZE = 996, 122 DEFAULT_MAX_REQ_SIZE_1 = sizeof(struct srp_cmd)/*48*/ + 123 SRP_MAX_ADD_CDB_LEN + 124 sizeof(struct srp_indirect_buf)/*20*/ + 125 128 * sizeof(struct srp_direct_buf)/*16*/, 126 DEFAULT_MAX_REQ_SIZE_2 = SRP_MAX_IMM_DATA_OFFSET + 127 sizeof(struct srp_imm_buf) + SRP_MAX_IMM_DATA, 128 DEFAULT_MAX_REQ_SIZE = DEFAULT_MAX_REQ_SIZE_1 > DEFAULT_MAX_REQ_SIZE_2 ? 129 DEFAULT_MAX_REQ_SIZE_1 : DEFAULT_MAX_REQ_SIZE_2, 130 131 MIN_MAX_RSP_SIZE = sizeof(struct srp_rsp)/*36*/ + 4, 132 DEFAULT_MAX_RSP_SIZE = 256, /* leaves 220 bytes for sense data */ 133 134 DEFAULT_MAX_RDMA_SIZE = 65536, 135}; 136 137/** 138 * enum srpt_command_state - SCSI command state managed by SRPT 139 * @SRPT_STATE_NEW: New command arrived and is being processed. 140 * @SRPT_STATE_NEED_DATA: Processing a write or bidir command and waiting 141 * for data arrival. 142 * @SRPT_STATE_DATA_IN: Data for the write or bidir command arrived and is 143 * being processed. 144 * @SRPT_STATE_CMD_RSP_SENT: SRP_RSP for SRP_CMD has been sent. 145 * @SRPT_STATE_MGMT: Processing a SCSI task management command. 146 * @SRPT_STATE_MGMT_RSP_SENT: SRP_RSP for SRP_TSK_MGMT has been sent. 147 * @SRPT_STATE_DONE: Command processing finished successfully, command 148 * processing has been aborted or command processing 149 * failed. 150 */ 151enum srpt_command_state { 152 SRPT_STATE_NEW = 0, 153 SRPT_STATE_NEED_DATA = 1, 154 SRPT_STATE_DATA_IN = 2, 155 SRPT_STATE_CMD_RSP_SENT = 3, 156 SRPT_STATE_MGMT = 4, 157 SRPT_STATE_MGMT_RSP_SENT = 5, 158 SRPT_STATE_DONE = 6, 159}; 160 161/** 162 * struct srpt_ioctx - shared SRPT I/O context information 163 * @cqe: Completion queue element. 164 * @buf: Pointer to the buffer. 165 * @dma: DMA address of the buffer. 166 * @offset: Offset of the first byte in @buf and @dma that is actually used. 167 * @index: Index of the I/O context in its ioctx_ring array. 168 */ 169struct srpt_ioctx { 170 struct ib_cqe cqe; 171 void *buf; 172 dma_addr_t dma; 173 uint32_t offset; 174 uint32_t index; 175}; 176 177/** 178 * struct srpt_recv_ioctx - SRPT receive I/O context 179 * @ioctx: See above. 180 * @wait_list: Node for insertion in srpt_rdma_ch.cmd_wait_list. 181 * @byte_len: Number of bytes in @ioctx.buf. 182 */ 183struct srpt_recv_ioctx { 184 struct srpt_ioctx ioctx; 185 struct list_head wait_list; 186 int byte_len; 187}; 188 189struct srpt_rw_ctx { 190 struct rdma_rw_ctx rw; 191 struct scatterlist *sg; 192 unsigned int nents; 193}; 194 195/** 196 * struct srpt_send_ioctx - SRPT send I/O context 197 * @ioctx: See above. 198 * @ch: Channel pointer. 199 * @recv_ioctx: Receive I/O context associated with this send I/O context. 200 * Only used for processing immediate data. 201 * @s_rw_ctx: @rw_ctxs points here if only a single rw_ctx is needed. 202 * @rw_ctxs: RDMA read/write contexts. 203 * @imm_sg: Scatterlist for immediate data. 204 * @rdma_cqe: RDMA completion queue element. 205 * @state: I/O context state. 206 * @cmd: Target core command data structure. 207 * @sense_data: SCSI sense data. 208 * @n_rdma: Number of work requests needed to transfer this ioctx. 209 * @n_rw_ctx: Size of rw_ctxs array. 210 * @queue_status_only: Send a SCSI status back to the initiator but no data. 211 * @sense_data: Sense data to be sent to the initiator. 212 */ 213struct srpt_send_ioctx { 214 struct srpt_ioctx ioctx; 215 struct srpt_rdma_ch *ch; 216 struct srpt_recv_ioctx *recv_ioctx; 217 218 struct srpt_rw_ctx s_rw_ctx; 219 struct srpt_rw_ctx *rw_ctxs; 220 221 struct scatterlist imm_sg; 222 223 struct ib_cqe rdma_cqe; 224 enum srpt_command_state state; 225 struct se_cmd cmd; 226 u8 n_rdma; 227 u8 n_rw_ctx; 228 bool queue_status_only; 229 u8 sense_data[TRANSPORT_SENSE_BUFFER]; 230}; 231 232/** 233 * enum rdma_ch_state - SRP channel state 234 * @CH_CONNECTING: QP is in RTR state; waiting for RTU. 235 * @CH_LIVE: QP is in RTS state. 236 * @CH_DISCONNECTING: DREQ has been sent and waiting for DREP or DREQ has 237 * been received. 238 * @CH_DRAINING: DREP has been received or waiting for DREP timed out 239 * and last work request has been queued. 240 * @CH_DISCONNECTED: Last completion has been received. 241 */ 242enum rdma_ch_state { 243 CH_CONNECTING, 244 CH_LIVE, 245 CH_DISCONNECTING, 246 CH_DRAINING, 247 CH_DISCONNECTED, 248}; 249 250/** 251 * struct srpt_rdma_ch - RDMA channel 252 * @nexus: I_T nexus this channel is associated with. 253 * @qp: IB queue pair used for communicating over this channel. 254 * @ib_cm: See below. 255 * @ib_cm.cm_id: IB CM ID associated with the channel. 256 * @rdma_cm: See below. 257 * @rdma_cm.cm_id: RDMA CM ID associated with the channel. 258 * @cq: IB completion queue for this channel. 259 * @cq_size: Number of CQEs in @cq. 260 * @zw_cqe: Zero-length write CQE. 261 * @rcu: RCU head. 262 * @kref: kref for this channel. 263 * @closed: Completion object that will be signaled as soon as a new 264 * channel object with the same identity can be created. 265 * @rq_size: IB receive queue size. 266 * @max_rsp_size: Maximum size of an RSP response message in bytes. 267 * @sq_wr_avail: number of work requests available in the send queue. 268 * @sport: pointer to the information of the HCA port used by this 269 * channel. 270 * @max_ti_iu_len: maximum target-to-initiator information unit length. 271 * @req_lim: request limit: maximum number of requests that may be sent 272 * by the initiator without having received a response. 273 * @req_lim_delta: Number of credits not yet sent back to the initiator. 274 * @imm_data_offset: Offset from start of SRP_CMD for immediate data. 275 * @spinlock: Protects free_list and state. 276 * @state: channel state. See also enum rdma_ch_state. 277 * @using_rdma_cm: Whether the RDMA/CM or IB/CM is used for this channel. 278 * @processing_wait_list: Whether or not cmd_wait_list is being processed. 279 * @rsp_buf_cache: kmem_cache for @ioctx_ring. 280 * @ioctx_ring: Send ring. 281 * @req_buf_cache: kmem_cache for @ioctx_recv_ring. 282 * @ioctx_recv_ring: Receive I/O context ring. 283 * @list: Node in srpt_nexus.ch_list. 284 * @cmd_wait_list: List of SCSI commands that arrived before the RTU event. This 285 * list contains struct srpt_ioctx elements and is protected 286 * against concurrent modification by the cm_id spinlock. 287 * @pkey: P_Key of the IB partition for this SRP channel. 288 * @sess: Session information associated with this SRP channel. 289 * @sess_name: Session name. 290 * @release_work: Allows scheduling of srpt_release_channel(). 291 */ 292struct srpt_rdma_ch { 293 struct srpt_nexus *nexus; 294 struct ib_qp *qp; 295 union { 296 struct { 297 struct ib_cm_id *cm_id; 298 } ib_cm; 299 struct { 300 struct rdma_cm_id *cm_id; 301 } rdma_cm; 302 }; 303 struct ib_cq *cq; 304 u32 cq_size; 305 struct ib_cqe zw_cqe; 306 struct rcu_head rcu; 307 struct kref kref; 308 struct completion *closed; 309 int rq_size; 310 u32 max_rsp_size; 311 atomic_t sq_wr_avail; 312 struct srpt_port *sport; 313 int max_ti_iu_len; 314 atomic_t req_lim; 315 atomic_t req_lim_delta; 316 u16 imm_data_offset; 317 spinlock_t spinlock; 318 enum rdma_ch_state state; 319 struct kmem_cache *rsp_buf_cache; 320 struct srpt_send_ioctx **ioctx_ring; 321 struct kmem_cache *req_buf_cache; 322 struct srpt_recv_ioctx **ioctx_recv_ring; 323 struct list_head list; 324 struct list_head cmd_wait_list; 325 uint16_t pkey; 326 bool using_rdma_cm; 327 bool processing_wait_list; 328 struct se_session *sess; 329 u8 sess_name[40]; 330 struct work_struct release_work; 331}; 332 333/** 334 * struct srpt_nexus - I_T nexus 335 * @rcu: RCU head for this data structure. 336 * @entry: srpt_port.nexus_list list node. 337 * @ch_list: struct srpt_rdma_ch list. Protected by srpt_port.mutex. 338 * @i_port_id: 128-bit initiator port identifier copied from SRP_LOGIN_REQ. 339 * @t_port_id: 128-bit target port identifier copied from SRP_LOGIN_REQ. 340 */ 341struct srpt_nexus { 342 struct rcu_head rcu; 343 struct list_head entry; 344 struct list_head ch_list; 345 u8 i_port_id[16]; 346 u8 t_port_id[16]; 347}; 348 349/** 350 * struct srpt_port_attrib - attributes for SRPT port 351 * @srp_max_rdma_size: Maximum size of SRP RDMA transfers for new connections. 352 * @srp_max_rsp_size: Maximum size of SRP response messages in bytes. 353 * @srp_sq_size: Shared receive queue (SRQ) size. 354 * @use_srq: Whether or not to use SRQ. 355 */ 356struct srpt_port_attrib { 357 u32 srp_max_rdma_size; 358 u32 srp_max_rsp_size; 359 u32 srp_sq_size; 360 bool use_srq; 361}; 362 363/** 364 * struct srpt_tpg - information about a single "target portal group" 365 * @entry: Entry in @sport_id->tpg_list. 366 * @sport_id: Port name this TPG is associated with. 367 * @tpg: LIO TPG data structure. 368 * 369 * Zero or more target portal groups are associated with each port name 370 * (srpt_port_id). With each TPG an ACL list is associated. 371 */ 372struct srpt_tpg { 373 struct list_head entry; 374 struct srpt_port_id *sport_id; 375 struct se_portal_group tpg; 376}; 377 378/** 379 * struct srpt_port_id - LIO RDMA port information 380 * @mutex: Protects @tpg_list changes. 381 * @tpg_list: TPGs associated with the RDMA port name. 382 * @wwn: WWN associated with the RDMA port name. 383 * @name: ASCII representation of the port name. 384 * 385 * Multiple sysfs directories can be associated with a single RDMA port. This 386 * data structure represents a single (port, name) pair. 387 */ 388struct srpt_port_id { 389 struct mutex mutex; 390 struct list_head tpg_list; 391 struct se_wwn wwn; 392 char name[64]; 393}; 394 395/** 396 * struct srpt_port - SRPT RDMA port information 397 * @sdev: backpointer to the HCA information. 398 * @mad_agent: per-port management datagram processing information. 399 * @enabled: Whether or not this target port is enabled. 400 * @port: one-based port number. 401 * @sm_lid: cached value of the port's sm_lid. 402 * @lid: cached value of the port's lid. 403 * @gid: cached value of the port's gid. 404 * @work: work structure for refreshing the aforementioned cached values. 405 * @guid_name: port name in GUID format. 406 * @guid_id: LIO target port information for the port name in GUID format. 407 * @gid_name: port name in GID format. 408 * @gid_id: LIO target port information for the port name in GID format. 409 * @port_attrib: Port attributes that can be accessed through configfs. 410 * @refcount: Number of objects associated with this port. 411 * @freed_channels: Completion that will be signaled once @refcount becomes 0. 412 * @mutex: Protects nexus_list. 413 * @nexus_list: Nexus list. See also srpt_nexus.entry. 414 */ 415struct srpt_port { 416 struct srpt_device *sdev; 417 struct ib_mad_agent *mad_agent; 418 bool enabled; 419 u8 port; 420 u32 sm_lid; 421 u32 lid; 422 union ib_gid gid; 423 struct work_struct work; 424 char guid_name[64]; 425 struct srpt_port_id *guid_id; 426 char gid_name[64]; 427 struct srpt_port_id *gid_id; 428 struct srpt_port_attrib port_attrib; 429 atomic_t refcount; 430 struct completion *freed_channels; 431 struct mutex mutex; 432 struct list_head nexus_list; 433}; 434 435/** 436 * struct srpt_device - information associated by SRPT with a single HCA 437 * @refcnt: Reference count for this device. 438 * @device: Backpointer to the struct ib_device managed by the IB core. 439 * @pd: IB protection domain. 440 * @lkey: L_Key (local key) with write access to all local memory. 441 * @srq: Per-HCA SRQ (shared receive queue). 442 * @cm_id: Connection identifier. 443 * @srq_size: SRQ size. 444 * @sdev_mutex: Serializes use_srq changes. 445 * @use_srq: Whether or not to use SRQ. 446 * @req_buf_cache: kmem_cache for @ioctx_ring buffers. 447 * @ioctx_ring: Per-HCA SRQ. 448 * @event_handler: Per-HCA asynchronous IB event handler. 449 * @list: Node in srpt_dev_list. 450 * @port: Information about the ports owned by this HCA. 451 */ 452struct srpt_device { 453 struct kref refcnt; 454 struct ib_device *device; 455 struct ib_pd *pd; 456 u32 lkey; 457 struct ib_srq *srq; 458 struct ib_cm_id *cm_id; 459 int srq_size; 460 struct mutex sdev_mutex; 461 bool use_srq; 462 struct kmem_cache *req_buf_cache; 463 struct srpt_recv_ioctx **ioctx_ring; 464 struct ib_event_handler event_handler; 465 struct list_head list; 466 struct srpt_port port[]; 467}; 468 469#endif /* IB_SRPT_H */ 470