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