1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * iSCSI lib definitions 4 * 5 * Copyright (C) 2006 Red Hat, Inc. All rights reserved. 6 * Copyright (C) 2004 - 2006 Mike Christie 7 * Copyright (C) 2004 - 2005 Dmitry Yusupov 8 * Copyright (C) 2004 - 2005 Alex Aizman 9 */ 10 #ifndef LIBISCSI_H 11 #define LIBISCSI_H 12 13 #include <linux/types.h> 14 #include <linux/wait.h> 15 #include <linux/mutex.h> 16 #include <linux/timer.h> 17 #include <linux/workqueue.h> 18 #include <linux/kfifo.h> 19 #include <linux/refcount.h> 20 #include <scsi/iscsi_proto.h> 21 #include <scsi/iscsi_if.h> 22 #include <scsi/scsi_cmnd.h> 23 #include <scsi/scsi_transport_iscsi.h> 24 25 struct scsi_transport_template; 26 struct scsi_host_template; 27 struct scsi_device; 28 struct Scsi_Host; 29 struct scsi_target; 30 struct scsi_cmnd; 31 struct socket; 32 struct iscsi_transport; 33 struct iscsi_cls_session; 34 struct iscsi_cls_conn; 35 struct iscsi_session; 36 struct iscsi_nopin; 37 struct device; 38 39 #define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */ 40 #define ISCSI_MGMT_CMDS_MAX 15 41 42 #define ISCSI_DEF_CMD_PER_LUN 32 43 44 /* Task Mgmt states */ 45 enum { 46 TMF_INITIAL, 47 TMF_QUEUED, 48 TMF_SUCCESS, 49 TMF_FAILED, 50 TMF_TIMEDOUT, 51 TMF_NOT_FOUND, 52 }; 53 54 #define ISID_SIZE 6 55 56 /* Connection suspend "bit" */ 57 #define ISCSI_SUSPEND_BIT 1 58 59 #define ISCSI_ITT_MASK 0x1fff 60 #define ISCSI_TOTAL_CMDS_MAX 4096 61 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */ 62 #define ISCSI_TOTAL_CMDS_MIN 16 63 #define ISCSI_AGE_SHIFT 28 64 #define ISCSI_AGE_MASK 0xf 65 66 #define ISCSI_ADDRESS_BUF_LEN 64 67 68 enum { 69 /* this is the maximum possible storage for AHSs */ 70 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) + 71 sizeof(struct iscsi_rlength_ahdr), 72 ISCSI_DIGEST_SIZE = sizeof(__u32), 73 }; 74 75 76 enum { 77 ISCSI_TASK_FREE, 78 ISCSI_TASK_COMPLETED, 79 ISCSI_TASK_PENDING, 80 ISCSI_TASK_RUNNING, 81 ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */ 82 ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */ 83 ISCSI_TASK_REQUEUE_SCSIQ, /* qcmd requeueing to scsi-ml */ 84 }; 85 86 struct iscsi_r2t_info { 87 __be32 ttt; /* copied from R2T */ 88 __be32 exp_statsn; /* copied from R2T */ 89 uint32_t data_length; /* copied from R2T */ 90 uint32_t data_offset; /* copied from R2T */ 91 int data_count; /* DATA-Out payload progress */ 92 int datasn; 93 /* LLDs should set/update these values */ 94 int sent; /* R2T sequence progress */ 95 }; 96 97 struct iscsi_task { 98 /* 99 * Because LLDs allocate their hdr differently, this is a pointer 100 * and length to that storage. It must be setup at session 101 * creation time. 102 */ 103 struct iscsi_hdr *hdr; 104 unsigned short hdr_max; 105 unsigned short hdr_len; /* accumulated size of hdr used */ 106 /* copied values in case we need to send tmfs */ 107 itt_t hdr_itt; 108 __be32 cmdsn; 109 struct scsi_lun lun; 110 111 int itt; /* this ITT */ 112 113 unsigned imm_count; /* imm-data (bytes) */ 114 /* offset in unsolicited stream (bytes); */ 115 struct iscsi_r2t_info unsol_r2t; 116 char *data; /* mgmt payload */ 117 unsigned data_count; 118 struct scsi_cmnd *sc; /* associated SCSI cmd*/ 119 struct iscsi_conn *conn; /* used connection */ 120 121 /* data processing tracking */ 122 unsigned long last_xfer; 123 unsigned long last_timeout; 124 bool have_checked_conn; 125 126 /* T10 protection information */ 127 bool protected; 128 129 /* state set/tested under session->lock */ 130 int state; 131 refcount_t refcount; 132 struct list_head running; /* running cmd list */ 133 void *dd_data; /* driver/transport data */ 134 }; 135 136 /* invalid scsi_task pointer */ 137 #define INVALID_SCSI_TASK (struct iscsi_task *)-1l 138 139 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task) 140 { 141 return task->unsol_r2t.data_length > task->unsol_r2t.sent; 142 } 143 144 static inline void* iscsi_next_hdr(struct iscsi_task *task) 145 { 146 return (void*)task->hdr + task->hdr_len; 147 } 148 149 static inline bool iscsi_task_is_completed(struct iscsi_task *task) 150 { 151 return task->state == ISCSI_TASK_COMPLETED || 152 task->state == ISCSI_TASK_ABRT_TMF || 153 task->state == ISCSI_TASK_ABRT_SESS_RECOV; 154 } 155 156 /* Private data associated with struct scsi_cmnd. */ 157 struct iscsi_cmd { 158 struct iscsi_task *task; 159 int age; 160 }; 161 162 static inline struct iscsi_cmd *iscsi_cmd(struct scsi_cmnd *cmd) 163 { 164 return scsi_cmd_priv(cmd); 165 } 166 167 /* Connection's states */ 168 enum { 169 ISCSI_CONN_INITIAL_STAGE, 170 ISCSI_CONN_STARTED, 171 ISCSI_CONN_STOPPED, 172 ISCSI_CONN_CLEANUP_WAIT, 173 }; 174 175 struct iscsi_conn { 176 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */ 177 void *dd_data; /* iscsi_transport data */ 178 struct iscsi_session *session; /* parent session */ 179 /* 180 * conn_stop() flag: stop to recover, stop to terminate 181 */ 182 int stop_stage; 183 struct timer_list transport_timer; 184 unsigned long last_recv; 185 unsigned long last_ping; 186 int ping_timeout; 187 int recv_timeout; 188 struct iscsi_task *ping_task; 189 190 /* iSCSI connection-wide sequencing */ 191 uint32_t exp_statsn; 192 uint32_t statsn; 193 194 /* control data */ 195 int id; /* CID */ 196 int c_stage; /* connection state */ 197 /* 198 * Preallocated buffer for pdus that have data but do not 199 * originate from scsi-ml. We never have two pdus using the 200 * buffer at the same time. It is only allocated to 201 * the default max recv size because the pdus we support 202 * should always fit in this buffer 203 */ 204 char *data; 205 struct iscsi_task *login_task; /* mtask used for login/text */ 206 struct iscsi_task *task; /* xmit task in progress */ 207 208 /* xmit */ 209 /* items must be added/deleted under frwd lock */ 210 struct list_head mgmtqueue; /* mgmt (control) xmit queue */ 211 struct list_head cmdqueue; /* data-path cmd queue */ 212 struct list_head requeue; /* tasks needing another run */ 213 struct work_struct xmitwork; /* per-conn. xmit workqueue */ 214 unsigned long suspend_tx; /* suspend Tx */ 215 unsigned long suspend_rx; /* suspend Rx */ 216 217 /* negotiated params */ 218 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/ 219 unsigned max_xmit_dlength; /* target_max_recv_dsl */ 220 int hdrdgst_en; 221 int datadgst_en; 222 int ifmarker_en; 223 int ofmarker_en; 224 /* values userspace uses to id a conn */ 225 int persistent_port; 226 char *persistent_address; 227 228 unsigned max_segment_size; 229 unsigned tcp_xmit_wsf; 230 unsigned tcp_recv_wsf; 231 uint16_t keepalive_tmo; 232 uint16_t local_port; 233 uint8_t tcp_timestamp_stat; 234 uint8_t tcp_nagle_disable; 235 uint8_t tcp_wsf_disable; 236 uint8_t tcp_timer_scale; 237 uint8_t tcp_timestamp_en; 238 uint8_t fragment_disable; 239 uint8_t ipv4_tos; 240 uint8_t ipv6_traffic_class; 241 uint8_t ipv6_flow_label; 242 uint8_t is_fw_assigned_ipv6; 243 char *local_ipaddr; 244 245 /* MIB-statistics */ 246 uint64_t txdata_octets; 247 uint64_t rxdata_octets; 248 uint32_t scsicmd_pdus_cnt; 249 uint32_t dataout_pdus_cnt; 250 uint32_t scsirsp_pdus_cnt; 251 uint32_t datain_pdus_cnt; 252 uint32_t r2t_pdus_cnt; 253 uint32_t tmfcmd_pdus_cnt; 254 int32_t tmfrsp_pdus_cnt; 255 256 /* custom statistics */ 257 uint32_t eh_abort_cnt; 258 uint32_t fmr_unalign_cnt; 259 }; 260 261 struct iscsi_pool { 262 struct kfifo queue; /* FIFO Queue */ 263 void **pool; /* Pool of elements */ 264 int max; /* Max number of elements */ 265 }; 266 267 /* Session's states */ 268 enum { 269 ISCSI_STATE_FREE = 1, 270 ISCSI_STATE_LOGGED_IN, 271 ISCSI_STATE_FAILED, 272 ISCSI_STATE_TERMINATE, 273 ISCSI_STATE_IN_RECOVERY, 274 ISCSI_STATE_RECOVERY_FAILED, 275 ISCSI_STATE_LOGGING_OUT, 276 }; 277 278 struct iscsi_session { 279 struct iscsi_cls_session *cls_session; 280 /* 281 * Syncs up the scsi eh thread with the iscsi eh thread when sending 282 * task management functions. This must be taken before the session 283 * and recv lock. 284 */ 285 struct mutex eh_mutex; 286 /* abort */ 287 wait_queue_head_t ehwait; /* used in eh_abort() */ 288 struct iscsi_tm tmhdr; 289 struct timer_list tmf_timer; 290 int tmf_state; /* see TMF_INITIAL, etc.*/ 291 struct iscsi_task *running_aborted_task; 292 293 /* iSCSI session-wide sequencing */ 294 uint32_t cmdsn; 295 uint32_t exp_cmdsn; 296 uint32_t max_cmdsn; 297 298 /* This tracks the reqs queued into the initiator */ 299 uint32_t queued_cmdsn; 300 301 /* configuration */ 302 int abort_timeout; 303 int lu_reset_timeout; 304 int tgt_reset_timeout; 305 int initial_r2t_en; 306 unsigned short max_r2t; 307 int imm_data_en; 308 unsigned first_burst; 309 unsigned max_burst; 310 int time2wait; 311 int time2retain; 312 int pdu_inorder_en; 313 int dataseq_inorder_en; 314 int erl; 315 int fast_abort; 316 int tpgt; 317 char *username; 318 char *username_in; 319 char *password; 320 char *password_in; 321 char *targetname; 322 char *targetalias; 323 char *ifacename; 324 char *initiatorname; 325 char *boot_root; 326 char *boot_nic; 327 char *boot_target; 328 char *portal_type; 329 char *discovery_parent_type; 330 uint16_t discovery_parent_idx; 331 uint16_t def_taskmgmt_tmo; 332 uint16_t tsid; 333 uint8_t auto_snd_tgt_disable; 334 uint8_t discovery_sess; 335 uint8_t chap_auth_en; 336 uint8_t discovery_logout_en; 337 uint8_t bidi_chap_en; 338 uint8_t discovery_auth_optional; 339 uint8_t isid[ISID_SIZE]; 340 341 /* control data */ 342 struct iscsi_transport *tt; 343 struct Scsi_Host *host; 344 struct iscsi_conn *leadconn; /* leading connection */ 345 /* Between the forward and the backward locks exists a strict locking 346 * hierarchy. The mutual exclusion zone protected by the forward lock 347 * can enclose the mutual exclusion zone protected by the backward lock 348 * but not vice versa. 349 */ 350 spinlock_t frwd_lock; /* protects session state, * 351 * cmdsn, queued_cmdsn * 352 * session resources: * 353 * - cmdpool kfifo_out , * 354 * - mgmtpool, queues */ 355 spinlock_t back_lock; /* protects cmdsn_exp * 356 * cmdsn_max, * 357 * cmdpool kfifo_in */ 358 int state; /* session state */ 359 int age; /* counts session re-opens */ 360 361 int scsi_cmds_max; /* max scsi commands */ 362 int cmds_max; /* size of cmds array */ 363 struct iscsi_task **cmds; /* Original Cmds arr */ 364 struct iscsi_pool cmdpool; /* PDU's pool */ 365 void *dd_data; /* LLD private data */ 366 }; 367 368 enum { 369 ISCSI_HOST_SETUP, 370 ISCSI_HOST_REMOVED, 371 }; 372 373 struct iscsi_host { 374 char *initiatorname; 375 /* hw address or netdev iscsi connection is bound to */ 376 char *hwaddress; 377 char *netdev; 378 379 wait_queue_head_t session_removal_wq; 380 /* protects sessions and state */ 381 spinlock_t lock; 382 int num_sessions; 383 int state; 384 385 struct workqueue_struct *workq; 386 }; 387 388 /* 389 * scsi host template 390 */ 391 extern int iscsi_eh_abort(struct scsi_cmnd *sc); 392 extern int iscsi_eh_recover_target(struct scsi_cmnd *sc); 393 extern int iscsi_eh_session_reset(struct scsi_cmnd *sc); 394 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc); 395 extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc); 396 extern enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc); 397 398 /* 399 * iSCSI host helpers. 400 */ 401 #define iscsi_host_priv(_shost) \ 402 (shost_priv(_shost) + sizeof(struct iscsi_host)) 403 404 extern int iscsi_host_set_param(struct Scsi_Host *shost, 405 enum iscsi_host_param param, char *buf, 406 int buflen); 407 extern int iscsi_host_get_param(struct Scsi_Host *shost, 408 enum iscsi_host_param param, char *buf); 409 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev); 410 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht, 411 int dd_data_size, 412 bool xmit_can_sleep); 413 extern void iscsi_host_remove(struct Scsi_Host *shost); 414 extern void iscsi_host_free(struct Scsi_Host *shost); 415 extern int iscsi_target_alloc(struct scsi_target *starget); 416 extern int iscsi_host_get_max_scsi_cmds(struct Scsi_Host *shost, 417 uint16_t requested_cmds_max); 418 419 /* 420 * session management 421 */ 422 extern struct iscsi_cls_session * 423 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost, 424 uint16_t, int, int, uint32_t, unsigned int); 425 extern void iscsi_session_teardown(struct iscsi_cls_session *); 426 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *); 427 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn, 428 enum iscsi_param param, char *buf, int buflen); 429 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session, 430 enum iscsi_param param, char *buf); 431 432 #define iscsi_session_printk(prefix, _sess, fmt, a...) \ 433 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a) 434 435 /* 436 * connection management 437 */ 438 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *, 439 int, uint32_t); 440 extern void iscsi_conn_teardown(struct iscsi_cls_conn *); 441 extern int iscsi_conn_start(struct iscsi_cls_conn *); 442 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int); 443 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *, 444 int); 445 extern void iscsi_conn_unbind(struct iscsi_cls_conn *cls_conn, bool is_active); 446 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err); 447 extern void iscsi_session_failure(struct iscsi_session *session, 448 enum iscsi_err err); 449 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn, 450 enum iscsi_param param, char *buf); 451 extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr, 452 enum iscsi_param param, char *buf); 453 extern void iscsi_suspend_tx(struct iscsi_conn *conn); 454 extern void iscsi_suspend_queue(struct iscsi_conn *conn); 455 extern void iscsi_conn_queue_work(struct iscsi_conn *conn); 456 457 #define iscsi_conn_printk(prefix, _c, fmt, a...) \ 458 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \ 459 fmt, ##a) 460 461 /* 462 * pdu and task processing 463 */ 464 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *); 465 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task, 466 struct iscsi_r2t_info *r2t, 467 struct iscsi_data *hdr); 468 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *, 469 char *, uint32_t); 470 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *, 471 char *, int); 472 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *, 473 char *, int); 474 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t); 475 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t); 476 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t); 477 extern void iscsi_requeue_task(struct iscsi_task *task); 478 extern void iscsi_put_task(struct iscsi_task *task); 479 extern void __iscsi_put_task(struct iscsi_task *task); 480 extern void __iscsi_get_task(struct iscsi_task *task); 481 extern void iscsi_complete_scsi_task(struct iscsi_task *task, 482 uint32_t exp_cmdsn, uint32_t max_cmdsn); 483 484 /* 485 * generic helpers 486 */ 487 extern void iscsi_pool_free(struct iscsi_pool *); 488 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int); 489 extern int iscsi_switch_str_param(char **, char *); 490 491 /* 492 * inline functions to deal with padding. 493 */ 494 static inline unsigned int 495 iscsi_padded(unsigned int len) 496 { 497 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1); 498 } 499 500 static inline unsigned int 501 iscsi_padding(unsigned int len) 502 { 503 len &= (ISCSI_PAD_LEN - 1); 504 if (len) 505 len = ISCSI_PAD_LEN - len; 506 return len; 507 } 508 509 #endif 510