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 flags */ 57 #define ISCSI_CONN_FLAG_SUSPEND_TX BIT(0) 58 #define ISCSI_CONN_FLAG_SUSPEND_RX BIT(1) 59 #define ISCSI_CONN_FLAG_BOUND BIT(2) 60 61 #define ISCSI_ITT_MASK 0x1fff 62 #define ISCSI_TOTAL_CMDS_MAX 4096 63 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */ 64 #define ISCSI_TOTAL_CMDS_MIN 16 65 #define ISCSI_AGE_SHIFT 28 66 #define ISCSI_AGE_MASK 0xf 67 68 #define ISCSI_ADDRESS_BUF_LEN 64 69 70 enum { 71 /* this is the maximum possible storage for AHSs */ 72 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) + 73 sizeof(struct iscsi_rlength_ahdr), 74 ISCSI_DIGEST_SIZE = sizeof(__u32), 75 }; 76 77 78 enum { 79 ISCSI_TASK_FREE, 80 ISCSI_TASK_COMPLETED, 81 ISCSI_TASK_PENDING, 82 ISCSI_TASK_RUNNING, 83 ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */ 84 ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */ 85 ISCSI_TASK_REQUEUE_SCSIQ, /* qcmd requeueing to scsi-ml */ 86 }; 87 88 struct iscsi_r2t_info { 89 __be32 ttt; /* copied from R2T */ 90 __be32 exp_statsn; /* copied from R2T */ 91 uint32_t data_length; /* copied from R2T */ 92 uint32_t data_offset; /* copied from R2T */ 93 int data_count; /* DATA-Out payload progress */ 94 int datasn; 95 /* LLDs should set/update these values */ 96 int sent; /* R2T sequence progress */ 97 }; 98 99 struct iscsi_task { 100 /* 101 * Because LLDs allocate their hdr differently, this is a pointer 102 * and length to that storage. It must be setup at session 103 * creation time. 104 */ 105 struct iscsi_hdr *hdr; 106 unsigned short hdr_max; 107 unsigned short hdr_len; /* accumulated size of hdr used */ 108 /* copied values in case we need to send tmfs */ 109 itt_t hdr_itt; 110 __be32 cmdsn; 111 struct scsi_lun lun; 112 113 int itt; /* this ITT */ 114 115 unsigned imm_count; /* imm-data (bytes) */ 116 /* offset in unsolicited stream (bytes); */ 117 struct iscsi_r2t_info unsol_r2t; 118 char *data; /* mgmt payload */ 119 unsigned data_count; 120 struct scsi_cmnd *sc; /* associated SCSI cmd*/ 121 struct iscsi_conn *conn; /* used connection */ 122 123 /* data processing tracking */ 124 unsigned long last_xfer; 125 unsigned long last_timeout; 126 bool have_checked_conn; 127 128 /* T10 protection information */ 129 bool protected; 130 131 /* state set/tested under session->lock */ 132 int state; 133 refcount_t refcount; 134 struct list_head running; /* running cmd list */ 135 void *dd_data; /* driver/transport data */ 136 }; 137 138 /* invalid scsi_task pointer */ 139 #define INVALID_SCSI_TASK (struct iscsi_task *)-1l 140 141 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task) 142 { 143 return task->unsol_r2t.data_length > task->unsol_r2t.sent; 144 } 145 146 static inline void* iscsi_next_hdr(struct iscsi_task *task) 147 { 148 return (void*)task->hdr + task->hdr_len; 149 } 150 151 static inline bool iscsi_task_is_completed(struct iscsi_task *task) 152 { 153 return task->state == ISCSI_TASK_COMPLETED || 154 task->state == ISCSI_TASK_ABRT_TMF || 155 task->state == ISCSI_TASK_ABRT_SESS_RECOV; 156 } 157 158 /* Private data associated with struct scsi_cmnd. */ 159 struct iscsi_cmd { 160 struct iscsi_task *task; 161 int age; 162 }; 163 164 static inline struct iscsi_cmd *iscsi_cmd(struct scsi_cmnd *cmd) 165 { 166 return scsi_cmd_priv(cmd); 167 } 168 169 /* Connection's states */ 170 enum { 171 ISCSI_CONN_INITIAL_STAGE, 172 ISCSI_CONN_STARTED, 173 ISCSI_CONN_STOPPED, 174 ISCSI_CONN_CLEANUP_WAIT, 175 }; 176 177 struct iscsi_conn { 178 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */ 179 void *dd_data; /* iscsi_transport data */ 180 struct iscsi_session *session; /* parent session */ 181 /* 182 * conn_stop() flag: stop to recover, stop to terminate 183 */ 184 int stop_stage; 185 struct timer_list transport_timer; 186 unsigned long last_recv; 187 unsigned long last_ping; 188 int ping_timeout; 189 int recv_timeout; 190 struct iscsi_task *ping_task; 191 192 /* iSCSI connection-wide sequencing */ 193 uint32_t exp_statsn; 194 uint32_t statsn; 195 196 /* control data */ 197 int id; /* CID */ 198 int c_stage; /* connection state */ 199 /* 200 * Preallocated buffer for pdus that have data but do not 201 * originate from scsi-ml. We never have two pdus using the 202 * buffer at the same time. It is only allocated to 203 * the default max recv size because the pdus we support 204 * should always fit in this buffer 205 */ 206 char *data; 207 struct iscsi_task *login_task; /* mtask used for login/text */ 208 struct iscsi_task *task; /* xmit task in progress */ 209 210 /* xmit */ 211 /* items must be added/deleted under frwd lock */ 212 struct list_head mgmtqueue; /* mgmt (control) xmit queue */ 213 struct list_head cmdqueue; /* data-path cmd queue */ 214 struct list_head requeue; /* tasks needing another run */ 215 struct work_struct xmitwork; /* per-conn. xmit workqueue */ 216 unsigned long flags; /* ISCSI_CONN_FLAGs */ 217 218 /* negotiated params */ 219 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/ 220 unsigned max_xmit_dlength; /* target_max_recv_dsl */ 221 int hdrdgst_en; 222 int datadgst_en; 223 int ifmarker_en; 224 int ofmarker_en; 225 /* values userspace uses to id a conn */ 226 int persistent_port; 227 char *persistent_address; 228 229 unsigned max_segment_size; 230 unsigned tcp_xmit_wsf; 231 unsigned tcp_recv_wsf; 232 uint16_t keepalive_tmo; 233 uint16_t local_port; 234 uint8_t tcp_timestamp_stat; 235 uint8_t tcp_nagle_disable; 236 uint8_t tcp_wsf_disable; 237 uint8_t tcp_timer_scale; 238 uint8_t tcp_timestamp_en; 239 uint8_t fragment_disable; 240 uint8_t ipv4_tos; 241 uint8_t ipv6_traffic_class; 242 uint8_t ipv6_flow_label; 243 uint8_t is_fw_assigned_ipv6; 244 char *local_ipaddr; 245 246 /* MIB-statistics */ 247 uint64_t txdata_octets; 248 uint64_t rxdata_octets; 249 uint32_t scsicmd_pdus_cnt; 250 uint32_t dataout_pdus_cnt; 251 uint32_t scsirsp_pdus_cnt; 252 uint32_t datain_pdus_cnt; 253 uint32_t r2t_pdus_cnt; 254 uint32_t tmfcmd_pdus_cnt; 255 int32_t tmfrsp_pdus_cnt; 256 257 /* custom statistics */ 258 uint32_t eh_abort_cnt; 259 uint32_t fmr_unalign_cnt; 260 }; 261 262 struct iscsi_pool { 263 struct kfifo queue; /* FIFO Queue */ 264 void **pool; /* Pool of elements */ 265 int max; /* Max number of elements */ 266 }; 267 268 /* Session's states */ 269 enum { 270 ISCSI_STATE_FREE = 1, 271 ISCSI_STATE_LOGGED_IN, 272 ISCSI_STATE_FAILED, 273 ISCSI_STATE_TERMINATE, 274 ISCSI_STATE_IN_RECOVERY, 275 ISCSI_STATE_RECOVERY_FAILED, 276 ISCSI_STATE_LOGGING_OUT, 277 }; 278 279 struct iscsi_session { 280 struct iscsi_cls_session *cls_session; 281 /* 282 * Syncs up the scsi eh thread with the iscsi eh thread when sending 283 * task management functions. This must be taken before the session 284 * and recv lock. 285 */ 286 struct mutex eh_mutex; 287 /* abort */ 288 wait_queue_head_t ehwait; /* used in eh_abort() */ 289 struct iscsi_tm tmhdr; 290 struct timer_list tmf_timer; 291 int tmf_state; /* see TMF_INITIAL, etc.*/ 292 struct iscsi_task *running_aborted_task; 293 294 /* iSCSI session-wide sequencing */ 295 uint32_t cmdsn; 296 uint32_t exp_cmdsn; 297 uint32_t max_cmdsn; 298 299 /* This tracks the reqs queued into the initiator */ 300 uint32_t queued_cmdsn; 301 302 /* configuration */ 303 int abort_timeout; 304 int lu_reset_timeout; 305 int tgt_reset_timeout; 306 int initial_r2t_en; 307 unsigned short max_r2t; 308 int imm_data_en; 309 unsigned first_burst; 310 unsigned max_burst; 311 int time2wait; 312 int time2retain; 313 int pdu_inorder_en; 314 int dataseq_inorder_en; 315 int erl; 316 int fast_abort; 317 int tpgt; 318 char *username; 319 char *username_in; 320 char *password; 321 char *password_in; 322 char *targetname; 323 char *targetalias; 324 char *ifacename; 325 char *initiatorname; 326 char *boot_root; 327 char *boot_nic; 328 char *boot_target; 329 char *portal_type; 330 char *discovery_parent_type; 331 uint16_t discovery_parent_idx; 332 uint16_t def_taskmgmt_tmo; 333 uint16_t tsid; 334 uint8_t auto_snd_tgt_disable; 335 uint8_t discovery_sess; 336 uint8_t chap_auth_en; 337 uint8_t discovery_logout_en; 338 uint8_t bidi_chap_en; 339 uint8_t discovery_auth_optional; 340 uint8_t isid[ISID_SIZE]; 341 342 /* control data */ 343 struct iscsi_transport *tt; 344 struct Scsi_Host *host; 345 struct iscsi_conn *leadconn; /* leading connection */ 346 /* Between the forward and the backward locks exists a strict locking 347 * hierarchy. The mutual exclusion zone protected by the forward lock 348 * can enclose the mutual exclusion zone protected by the backward lock 349 * but not vice versa. 350 */ 351 spinlock_t frwd_lock; /* protects session state, * 352 * cmdsn, queued_cmdsn * 353 * session resources: * 354 * - cmdpool kfifo_out , * 355 * - mgmtpool, queues */ 356 spinlock_t back_lock; /* protects cmdsn_exp * 357 * cmdsn_max, * 358 * cmdpool kfifo_in */ 359 int state; /* session state */ 360 int age; /* counts session re-opens */ 361 362 int scsi_cmds_max; /* max scsi commands */ 363 int cmds_max; /* size of cmds array */ 364 struct iscsi_task **cmds; /* Original Cmds arr */ 365 struct iscsi_pool cmdpool; /* PDU's pool */ 366 void *dd_data; /* LLD private data */ 367 }; 368 369 enum { 370 ISCSI_HOST_SETUP, 371 ISCSI_HOST_REMOVED, 372 }; 373 374 struct iscsi_host { 375 char *initiatorname; 376 /* hw address or netdev iscsi connection is bound to */ 377 char *hwaddress; 378 char *netdev; 379 380 wait_queue_head_t session_removal_wq; 381 /* protects sessions and state */ 382 spinlock_t lock; 383 int num_sessions; 384 int state; 385 386 struct workqueue_struct *workq; 387 }; 388 389 /* 390 * scsi host template 391 */ 392 extern int iscsi_eh_abort(struct scsi_cmnd *sc); 393 extern int iscsi_eh_recover_target(struct scsi_cmnd *sc); 394 extern int iscsi_eh_session_reset(struct scsi_cmnd *sc); 395 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc); 396 extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc); 397 extern enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc); 398 399 /* 400 * iSCSI host helpers. 401 */ 402 #define iscsi_host_priv(_shost) \ 403 (shost_priv(_shost) + sizeof(struct iscsi_host)) 404 405 extern int iscsi_host_set_param(struct Scsi_Host *shost, 406 enum iscsi_host_param param, char *buf, 407 int buflen); 408 extern int iscsi_host_get_param(struct Scsi_Host *shost, 409 enum iscsi_host_param param, char *buf); 410 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev); 411 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht, 412 int dd_data_size, 413 bool xmit_can_sleep); 414 extern void iscsi_host_remove(struct Scsi_Host *shost); 415 extern void iscsi_host_free(struct Scsi_Host *shost); 416 extern int iscsi_target_alloc(struct scsi_target *starget); 417 extern int iscsi_host_get_max_scsi_cmds(struct Scsi_Host *shost, 418 uint16_t requested_cmds_max); 419 420 /* 421 * session management 422 */ 423 extern struct iscsi_cls_session * 424 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost, 425 uint16_t, int, int, uint32_t, unsigned int); 426 extern void iscsi_session_teardown(struct iscsi_cls_session *); 427 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *); 428 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn, 429 enum iscsi_param param, char *buf, int buflen); 430 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session, 431 enum iscsi_param param, char *buf); 432 433 #define iscsi_session_printk(prefix, _sess, fmt, a...) \ 434 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a) 435 436 /* 437 * connection management 438 */ 439 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *, 440 int, uint32_t); 441 extern void iscsi_conn_teardown(struct iscsi_cls_conn *); 442 extern int iscsi_conn_start(struct iscsi_cls_conn *); 443 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int); 444 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *, 445 int); 446 extern void iscsi_conn_unbind(struct iscsi_cls_conn *cls_conn, bool is_active); 447 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err); 448 extern void iscsi_session_failure(struct iscsi_session *session, 449 enum iscsi_err err); 450 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn, 451 enum iscsi_param param, char *buf); 452 extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr, 453 enum iscsi_param param, char *buf); 454 extern void iscsi_suspend_tx(struct iscsi_conn *conn); 455 extern void iscsi_suspend_queue(struct iscsi_conn *conn); 456 extern void iscsi_conn_queue_work(struct iscsi_conn *conn); 457 458 #define iscsi_conn_printk(prefix, _c, fmt, a...) \ 459 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \ 460 fmt, ##a) 461 462 /* 463 * pdu and task processing 464 */ 465 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *); 466 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task, 467 struct iscsi_r2t_info *r2t, 468 struct iscsi_data *hdr); 469 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *, 470 char *, uint32_t); 471 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *, 472 char *, int); 473 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *, 474 char *, int); 475 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t); 476 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t); 477 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t); 478 extern void iscsi_requeue_task(struct iscsi_task *task); 479 extern void iscsi_put_task(struct iscsi_task *task); 480 extern void __iscsi_put_task(struct iscsi_task *task); 481 extern void __iscsi_get_task(struct iscsi_task *task); 482 extern void iscsi_complete_scsi_task(struct iscsi_task *task, 483 uint32_t exp_cmdsn, uint32_t max_cmdsn); 484 485 /* 486 * generic helpers 487 */ 488 extern void iscsi_pool_free(struct iscsi_pool *); 489 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int); 490 extern int iscsi_switch_str_param(char **, char *); 491 492 /* 493 * inline functions to deal with padding. 494 */ 495 static inline unsigned int 496 iscsi_padded(unsigned int len) 497 { 498 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1); 499 } 500 501 static inline unsigned int 502 iscsi_padding(unsigned int len) 503 { 504 len &= (ISCSI_PAD_LEN - 1); 505 if (len) 506 len = ISCSI_PAD_LEN - len; 507 return len; 508 } 509 510 #endif 511