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 58 struct srpt_nexus; 59 60 enum { 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 * An experimentally determined value that avoids that QP creation 110 * fails due to "swiotlb buffer is full" on systems using the swiotlb. 111 */ 112 SRPT_MAX_SG_PER_WQE = 16, 113 114 MIN_SRPT_SQ_SIZE = 16, 115 DEF_SRPT_SQ_SIZE = 4096, 116 MAX_SRPT_RQ_SIZE = 128, 117 MIN_SRPT_SRQ_SIZE = 4, 118 DEFAULT_SRPT_SRQ_SIZE = 4095, 119 MAX_SRPT_SRQ_SIZE = 65535, 120 MAX_SRPT_RDMA_SIZE = 1U << 24, 121 MAX_SRPT_RSP_SIZE = 1024, 122 123 SRP_MAX_ADD_CDB_LEN = 16, 124 SRP_MAX_IMM_DATA_OFFSET = 80, 125 SRP_MAX_IMM_DATA = 8 * 1024, 126 MIN_MAX_REQ_SIZE = 996, 127 DEFAULT_MAX_REQ_SIZE_1 = sizeof(struct srp_cmd)/*48*/ + 128 SRP_MAX_ADD_CDB_LEN + 129 sizeof(struct srp_indirect_buf)/*20*/ + 130 128 * sizeof(struct srp_direct_buf)/*16*/, 131 DEFAULT_MAX_REQ_SIZE_2 = SRP_MAX_IMM_DATA_OFFSET + 132 sizeof(struct srp_imm_buf) + SRP_MAX_IMM_DATA, 133 DEFAULT_MAX_REQ_SIZE = DEFAULT_MAX_REQ_SIZE_1 > DEFAULT_MAX_REQ_SIZE_2 ? 134 DEFAULT_MAX_REQ_SIZE_1 : DEFAULT_MAX_REQ_SIZE_2, 135 136 MIN_MAX_RSP_SIZE = sizeof(struct srp_rsp)/*36*/ + 4, 137 DEFAULT_MAX_RSP_SIZE = 256, /* leaves 220 bytes for sense data */ 138 139 DEFAULT_MAX_RDMA_SIZE = 65536, 140 }; 141 142 /** 143 * enum srpt_command_state - SCSI command state managed by SRPT 144 * @SRPT_STATE_NEW: New command arrived and is being processed. 145 * @SRPT_STATE_NEED_DATA: Processing a write or bidir command and waiting 146 * for data arrival. 147 * @SRPT_STATE_DATA_IN: Data for the write or bidir command arrived and is 148 * being processed. 149 * @SRPT_STATE_CMD_RSP_SENT: SRP_RSP for SRP_CMD has been sent. 150 * @SRPT_STATE_MGMT: Processing a SCSI task management command. 151 * @SRPT_STATE_MGMT_RSP_SENT: SRP_RSP for SRP_TSK_MGMT has been sent. 152 * @SRPT_STATE_DONE: Command processing finished successfully, command 153 * processing has been aborted or command processing 154 * failed. 155 */ 156 enum srpt_command_state { 157 SRPT_STATE_NEW = 0, 158 SRPT_STATE_NEED_DATA = 1, 159 SRPT_STATE_DATA_IN = 2, 160 SRPT_STATE_CMD_RSP_SENT = 3, 161 SRPT_STATE_MGMT = 4, 162 SRPT_STATE_MGMT_RSP_SENT = 5, 163 SRPT_STATE_DONE = 6, 164 }; 165 166 /** 167 * struct srpt_ioctx - shared SRPT I/O context information 168 * @cqe: Completion queue element. 169 * @buf: Pointer to the buffer. 170 * @dma: DMA address of the buffer. 171 * @offset: Offset of the first byte in @buf and @dma that is actually used. 172 * @index: Index of the I/O context in its ioctx_ring array. 173 */ 174 struct srpt_ioctx { 175 struct ib_cqe cqe; 176 void *buf; 177 dma_addr_t dma; 178 uint32_t offset; 179 uint32_t index; 180 }; 181 182 /** 183 * struct srpt_recv_ioctx - SRPT receive I/O context 184 * @ioctx: See above. 185 * @wait_list: Node for insertion in srpt_rdma_ch.cmd_wait_list. 186 * @byte_len: Number of bytes in @ioctx.buf. 187 */ 188 struct srpt_recv_ioctx { 189 struct srpt_ioctx ioctx; 190 struct list_head wait_list; 191 int byte_len; 192 }; 193 194 struct srpt_rw_ctx { 195 struct rdma_rw_ctx rw; 196 struct scatterlist *sg; 197 unsigned int nents; 198 }; 199 200 /** 201 * struct srpt_send_ioctx - SRPT send I/O context 202 * @ioctx: See above. 203 * @ch: Channel pointer. 204 * @recv_ioctx: Receive I/O context associated with this send I/O context. 205 * Only used for processing immediate data. 206 * @s_rw_ctx: @rw_ctxs points here if only a single rw_ctx is needed. 207 * @rw_ctxs: RDMA read/write contexts. 208 * @imm_sg: Scatterlist for immediate data. 209 * @rdma_cqe: RDMA completion queue element. 210 * @state: I/O context state. 211 * @cmd: Target core command data structure. 212 * @sense_data: SCSI sense data. 213 * @n_rdma: Number of work requests needed to transfer this ioctx. 214 * @n_rw_ctx: Size of rw_ctxs array. 215 * @queue_status_only: Send a SCSI status back to the initiator but no data. 216 * @sense_data: Sense data to be sent to the initiator. 217 */ 218 struct srpt_send_ioctx { 219 struct srpt_ioctx ioctx; 220 struct srpt_rdma_ch *ch; 221 struct srpt_recv_ioctx *recv_ioctx; 222 223 struct srpt_rw_ctx s_rw_ctx; 224 struct srpt_rw_ctx *rw_ctxs; 225 226 struct scatterlist imm_sg; 227 228 struct ib_cqe rdma_cqe; 229 enum srpt_command_state state; 230 struct se_cmd cmd; 231 u8 n_rdma; 232 u8 n_rw_ctx; 233 bool queue_status_only; 234 u8 sense_data[TRANSPORT_SENSE_BUFFER]; 235 }; 236 237 /** 238 * enum rdma_ch_state - SRP channel state 239 * @CH_CONNECTING: QP is in RTR state; waiting for RTU. 240 * @CH_LIVE: QP is in RTS state. 241 * @CH_DISCONNECTING: DREQ has been sent and waiting for DREP or DREQ has 242 * been received. 243 * @CH_DRAINING: DREP has been received or waiting for DREP timed out 244 * and last work request has been queued. 245 * @CH_DISCONNECTED: Last completion has been received. 246 */ 247 enum rdma_ch_state { 248 CH_CONNECTING, 249 CH_LIVE, 250 CH_DISCONNECTING, 251 CH_DRAINING, 252 CH_DISCONNECTED, 253 }; 254 255 /** 256 * struct srpt_rdma_ch - RDMA channel 257 * @nexus: I_T nexus this channel is associated with. 258 * @qp: IB queue pair used for communicating over this channel. 259 * @ib_cm: See below. 260 * @ib_cm.cm_id: IB CM ID associated with the channel. 261 * @rdma_cm: See below. 262 * @rdma_cm.cm_id: RDMA CM ID associated with the channel. 263 * @cq: IB completion queue for this channel. 264 * @zw_cqe: Zero-length write CQE. 265 * @rcu: RCU head. 266 * @kref: kref for this channel. 267 * @closed: Completion object that will be signaled as soon as a new 268 * channel object with the same identity can be created. 269 * @rq_size: IB receive queue size. 270 * @max_rsp_size: Maximum size of an RSP response message in bytes. 271 * @sq_wr_avail: number of work requests available in the send queue. 272 * @sport: pointer to the information of the HCA port used by this 273 * channel. 274 * @max_ti_iu_len: maximum target-to-initiator information unit length. 275 * @req_lim: request limit: maximum number of requests that may be sent 276 * by the initiator without having received a response. 277 * @req_lim_delta: Number of credits not yet sent back to the initiator. 278 * @imm_data_offset: Offset from start of SRP_CMD for immediate data. 279 * @spinlock: Protects free_list and state. 280 * @state: channel state. See also enum rdma_ch_state. 281 * @using_rdma_cm: Whether the RDMA/CM or IB/CM is used for this channel. 282 * @processing_wait_list: Whether or not cmd_wait_list is being processed. 283 * @rsp_buf_cache: kmem_cache for @ioctx_ring. 284 * @ioctx_ring: Send ring. 285 * @req_buf_cache: kmem_cache for @ioctx_recv_ring. 286 * @ioctx_recv_ring: Receive I/O context ring. 287 * @list: Node in srpt_nexus.ch_list. 288 * @cmd_wait_list: List of SCSI commands that arrived before the RTU event. This 289 * list contains struct srpt_ioctx elements and is protected 290 * against concurrent modification by the cm_id spinlock. 291 * @pkey: P_Key of the IB partition for this SRP channel. 292 * @sess: Session information associated with this SRP channel. 293 * @sess_name: Session name. 294 * @release_work: Allows scheduling of srpt_release_channel(). 295 */ 296 struct srpt_rdma_ch { 297 struct srpt_nexus *nexus; 298 struct ib_qp *qp; 299 union { 300 struct { 301 struct ib_cm_id *cm_id; 302 } ib_cm; 303 struct { 304 struct rdma_cm_id *cm_id; 305 } rdma_cm; 306 }; 307 struct ib_cq *cq; 308 struct ib_cqe zw_cqe; 309 struct rcu_head rcu; 310 struct kref kref; 311 struct completion *closed; 312 int rq_size; 313 u32 max_rsp_size; 314 atomic_t sq_wr_avail; 315 struct srpt_port *sport; 316 int max_ti_iu_len; 317 atomic_t req_lim; 318 atomic_t req_lim_delta; 319 u16 imm_data_offset; 320 spinlock_t spinlock; 321 enum rdma_ch_state state; 322 struct kmem_cache *rsp_buf_cache; 323 struct srpt_send_ioctx **ioctx_ring; 324 struct kmem_cache *req_buf_cache; 325 struct srpt_recv_ioctx **ioctx_recv_ring; 326 struct list_head list; 327 struct list_head cmd_wait_list; 328 uint16_t pkey; 329 bool using_rdma_cm; 330 bool processing_wait_list; 331 struct se_session *sess; 332 u8 sess_name[40]; 333 struct work_struct release_work; 334 }; 335 336 /** 337 * struct srpt_nexus - I_T nexus 338 * @rcu: RCU head for this data structure. 339 * @entry: srpt_port.nexus_list list node. 340 * @ch_list: struct srpt_rdma_ch list. Protected by srpt_port.mutex. 341 * @i_port_id: 128-bit initiator port identifier copied from SRP_LOGIN_REQ. 342 * @t_port_id: 128-bit target port identifier copied from SRP_LOGIN_REQ. 343 */ 344 struct srpt_nexus { 345 struct rcu_head rcu; 346 struct list_head entry; 347 struct list_head ch_list; 348 u8 i_port_id[16]; 349 u8 t_port_id[16]; 350 }; 351 352 /** 353 * struct srpt_port_attib - attributes for SRPT port 354 * @srp_max_rdma_size: Maximum size of SRP RDMA transfers for new connections. 355 * @srp_max_rsp_size: Maximum size of SRP response messages in bytes. 356 * @srp_sq_size: Shared receive queue (SRQ) size. 357 * @use_srq: Whether or not to use SRQ. 358 */ 359 struct srpt_port_attrib { 360 u32 srp_max_rdma_size; 361 u32 srp_max_rsp_size; 362 u32 srp_sq_size; 363 bool use_srq; 364 }; 365 366 /** 367 * struct srpt_tpg - information about a single "target portal group" 368 * @entry: Entry in @sport_id->tpg_list. 369 * @sport_id: Port name this TPG is associated with. 370 * @tpg: LIO TPG data structure. 371 * 372 * Zero or more target portal groups are associated with each port name 373 * (srpt_port_id). With each TPG an ACL list is associated. 374 */ 375 struct srpt_tpg { 376 struct list_head entry; 377 struct srpt_port_id *sport_id; 378 struct se_portal_group tpg; 379 }; 380 381 /** 382 * struct srpt_port_id - information about an RDMA port name 383 * @mutex: Protects @tpg_list changes. 384 * @tpg_list: TPGs associated with the RDMA port name. 385 * @wwn: WWN associated with the RDMA port name. 386 * @name: ASCII representation of the port name. 387 * 388 * Multiple sysfs directories can be associated with a single RDMA port. This 389 * data structure represents a single (port, name) pair. 390 */ 391 struct srpt_port_id { 392 struct mutex mutex; 393 struct list_head tpg_list; 394 struct se_wwn wwn; 395 char name[64]; 396 }; 397 398 /** 399 * struct srpt_port - information associated by SRPT with a single IB port 400 * @sdev: backpointer to the HCA information. 401 * @mad_agent: per-port management datagram processing information. 402 * @enabled: Whether or not this target port is enabled. 403 * @port: one-based port number. 404 * @sm_lid: cached value of the port's sm_lid. 405 * @lid: cached value of the port's lid. 406 * @gid: cached value of the port's gid. 407 * @work: work structure for refreshing the aforementioned cached values. 408 * @port_guid_id: target port GUID 409 * @port_gid_id: target port GID 410 * @port_attrib: Port attributes that can be accessed through configfs. 411 * @refcount: Number of objects associated with this port. 412 * @freed_channels: Completion that will be signaled once @refcount becomes 0. 413 * @mutex: Protects nexus_list. 414 * @nexus_list: Nexus list. See also srpt_nexus.entry. 415 */ 416 struct srpt_port { 417 struct srpt_device *sdev; 418 struct ib_mad_agent *mad_agent; 419 bool enabled; 420 u8 port; 421 u32 sm_lid; 422 u32 lid; 423 union ib_gid gid; 424 struct work_struct work; 425 struct srpt_port_id port_guid_id; 426 struct srpt_port_id port_gid_id; 427 struct srpt_port_attrib port_attrib; 428 atomic_t refcount; 429 struct completion *freed_channels; 430 struct mutex mutex; 431 struct list_head nexus_list; 432 }; 433 434 /** 435 * struct srpt_device - information associated by SRPT with a single HCA 436 * @device: Backpointer to the struct ib_device managed by the IB core. 437 * @pd: IB protection domain. 438 * @lkey: L_Key (local key) with write access to all local memory. 439 * @srq: Per-HCA SRQ (shared receive queue). 440 * @cm_id: Connection identifier. 441 * @srq_size: SRQ size. 442 * @sdev_mutex: Serializes use_srq changes. 443 * @use_srq: Whether or not to use SRQ. 444 * @req_buf_cache: kmem_cache for @ioctx_ring buffers. 445 * @ioctx_ring: Per-HCA SRQ. 446 * @event_handler: Per-HCA asynchronous IB event handler. 447 * @list: Node in srpt_dev_list. 448 * @port: Information about the ports owned by this HCA. 449 */ 450 struct srpt_device { 451 struct ib_device *device; 452 struct ib_pd *pd; 453 u32 lkey; 454 struct ib_srq *srq; 455 struct ib_cm_id *cm_id; 456 int srq_size; 457 struct mutex sdev_mutex; 458 bool use_srq; 459 struct kmem_cache *req_buf_cache; 460 struct srpt_recv_ioctx **ioctx_ring; 461 struct ib_event_handler event_handler; 462 struct list_head list; 463 struct srpt_port port[]; 464 }; 465 466 #endif /* IB_SRPT_H */ 467