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 /* Connection's states */ 149 enum { 150 ISCSI_CONN_INITIAL_STAGE, 151 ISCSI_CONN_STARTED, 152 ISCSI_CONN_STOPPED, 153 ISCSI_CONN_CLEANUP_WAIT, 154 }; 155 156 struct iscsi_conn { 157 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */ 158 void *dd_data; /* iscsi_transport data */ 159 struct iscsi_session *session; /* parent session */ 160 /* 161 * conn_stop() flag: stop to recover, stop to terminate 162 */ 163 int stop_stage; 164 struct timer_list transport_timer; 165 unsigned long last_recv; 166 unsigned long last_ping; 167 int ping_timeout; 168 int recv_timeout; 169 struct iscsi_task *ping_task; 170 171 /* iSCSI connection-wide sequencing */ 172 uint32_t exp_statsn; 173 uint32_t statsn; 174 175 /* control data */ 176 int id; /* CID */ 177 int c_stage; /* connection state */ 178 /* 179 * Preallocated buffer for pdus that have data but do not 180 * originate from scsi-ml. We never have two pdus using the 181 * buffer at the same time. It is only allocated to 182 * the default max recv size because the pdus we support 183 * should always fit in this buffer 184 */ 185 char *data; 186 struct iscsi_task *login_task; /* mtask used for login/text */ 187 struct iscsi_task *task; /* xmit task in progress */ 188 189 /* xmit */ 190 /* items must be added/deleted under frwd lock */ 191 struct list_head mgmtqueue; /* mgmt (control) xmit queue */ 192 struct list_head cmdqueue; /* data-path cmd queue */ 193 struct list_head requeue; /* tasks needing another run */ 194 struct work_struct xmitwork; /* per-conn. xmit workqueue */ 195 unsigned long suspend_tx; /* suspend Tx */ 196 unsigned long suspend_rx; /* suspend Rx */ 197 198 /* abort */ 199 wait_queue_head_t ehwait; /* used in eh_abort() */ 200 struct iscsi_tm tmhdr; 201 struct timer_list tmf_timer; 202 int tmf_state; /* see TMF_INITIAL, etc.*/ 203 204 /* negotiated params */ 205 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/ 206 unsigned max_xmit_dlength; /* target_max_recv_dsl */ 207 int hdrdgst_en; 208 int datadgst_en; 209 int ifmarker_en; 210 int ofmarker_en; 211 /* values userspace uses to id a conn */ 212 int persistent_port; 213 char *persistent_address; 214 215 unsigned max_segment_size; 216 unsigned tcp_xmit_wsf; 217 unsigned tcp_recv_wsf; 218 uint16_t keepalive_tmo; 219 uint16_t local_port; 220 uint8_t tcp_timestamp_stat; 221 uint8_t tcp_nagle_disable; 222 uint8_t tcp_wsf_disable; 223 uint8_t tcp_timer_scale; 224 uint8_t tcp_timestamp_en; 225 uint8_t fragment_disable; 226 uint8_t ipv4_tos; 227 uint8_t ipv6_traffic_class; 228 uint8_t ipv6_flow_label; 229 uint8_t is_fw_assigned_ipv6; 230 char *local_ipaddr; 231 232 /* MIB-statistics */ 233 uint64_t txdata_octets; 234 uint64_t rxdata_octets; 235 uint32_t scsicmd_pdus_cnt; 236 uint32_t dataout_pdus_cnt; 237 uint32_t scsirsp_pdus_cnt; 238 uint32_t datain_pdus_cnt; 239 uint32_t r2t_pdus_cnt; 240 uint32_t tmfcmd_pdus_cnt; 241 int32_t tmfrsp_pdus_cnt; 242 243 /* custom statistics */ 244 uint32_t eh_abort_cnt; 245 uint32_t fmr_unalign_cnt; 246 }; 247 248 struct iscsi_pool { 249 struct kfifo queue; /* FIFO Queue */ 250 void **pool; /* Pool of elements */ 251 int max; /* Max number of elements */ 252 }; 253 254 /* Session's states */ 255 enum { 256 ISCSI_STATE_FREE = 1, 257 ISCSI_STATE_LOGGED_IN, 258 ISCSI_STATE_FAILED, 259 ISCSI_STATE_TERMINATE, 260 ISCSI_STATE_IN_RECOVERY, 261 ISCSI_STATE_RECOVERY_FAILED, 262 ISCSI_STATE_LOGGING_OUT, 263 }; 264 265 struct iscsi_session { 266 struct iscsi_cls_session *cls_session; 267 /* 268 * Syncs up the scsi eh thread with the iscsi eh thread when sending 269 * task management functions. This must be taken before the session 270 * and recv lock. 271 */ 272 struct mutex eh_mutex; 273 274 /* iSCSI session-wide sequencing */ 275 uint32_t cmdsn; 276 uint32_t exp_cmdsn; 277 uint32_t max_cmdsn; 278 279 /* This tracks the reqs queued into the initiator */ 280 uint32_t queued_cmdsn; 281 282 /* configuration */ 283 int abort_timeout; 284 int lu_reset_timeout; 285 int tgt_reset_timeout; 286 int initial_r2t_en; 287 unsigned short max_r2t; 288 int imm_data_en; 289 unsigned first_burst; 290 unsigned max_burst; 291 int time2wait; 292 int time2retain; 293 int pdu_inorder_en; 294 int dataseq_inorder_en; 295 int erl; 296 int fast_abort; 297 int tpgt; 298 char *username; 299 char *username_in; 300 char *password; 301 char *password_in; 302 char *targetname; 303 char *targetalias; 304 char *ifacename; 305 char *initiatorname; 306 char *boot_root; 307 char *boot_nic; 308 char *boot_target; 309 char *portal_type; 310 char *discovery_parent_type; 311 uint16_t discovery_parent_idx; 312 uint16_t def_taskmgmt_tmo; 313 uint16_t tsid; 314 uint8_t auto_snd_tgt_disable; 315 uint8_t discovery_sess; 316 uint8_t chap_auth_en; 317 uint8_t discovery_logout_en; 318 uint8_t bidi_chap_en; 319 uint8_t discovery_auth_optional; 320 uint8_t isid[ISID_SIZE]; 321 322 /* control data */ 323 struct iscsi_transport *tt; 324 struct Scsi_Host *host; 325 struct iscsi_conn *leadconn; /* leading connection */ 326 /* Between the forward and the backward locks exists a strict locking 327 * hierarchy. The mutual exclusion zone protected by the forward lock 328 * can enclose the mutual exclusion zone protected by the backward lock 329 * but not vice versa. 330 */ 331 spinlock_t frwd_lock; /* protects session state, * 332 * cmdsn, queued_cmdsn * 333 * session resources: * 334 * - cmdpool kfifo_out , * 335 * - mgmtpool, queues */ 336 spinlock_t back_lock; /* protects cmdsn_exp * 337 * cmdsn_max, * 338 * cmdpool kfifo_in */ 339 int state; /* session state */ 340 int age; /* counts session re-opens */ 341 342 int scsi_cmds_max; /* max scsi commands */ 343 int cmds_max; /* size of cmds array */ 344 struct iscsi_task **cmds; /* Original Cmds arr */ 345 struct iscsi_pool cmdpool; /* PDU's pool */ 346 void *dd_data; /* LLD private data */ 347 }; 348 349 enum { 350 ISCSI_HOST_SETUP, 351 ISCSI_HOST_REMOVED, 352 }; 353 354 struct iscsi_host { 355 char *initiatorname; 356 /* hw address or netdev iscsi connection is bound to */ 357 char *hwaddress; 358 char *netdev; 359 360 wait_queue_head_t session_removal_wq; 361 /* protects sessions and state */ 362 spinlock_t lock; 363 int num_sessions; 364 int state; 365 366 struct workqueue_struct *workq; 367 char workq_name[20]; 368 }; 369 370 /* 371 * scsi host template 372 */ 373 extern int iscsi_eh_abort(struct scsi_cmnd *sc); 374 extern int iscsi_eh_recover_target(struct scsi_cmnd *sc); 375 extern int iscsi_eh_session_reset(struct scsi_cmnd *sc); 376 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc); 377 extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc); 378 extern enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc); 379 380 /* 381 * iSCSI host helpers. 382 */ 383 #define iscsi_host_priv(_shost) \ 384 (shost_priv(_shost) + sizeof(struct iscsi_host)) 385 386 extern int iscsi_host_set_param(struct Scsi_Host *shost, 387 enum iscsi_host_param param, char *buf, 388 int buflen); 389 extern int iscsi_host_get_param(struct Scsi_Host *shost, 390 enum iscsi_host_param param, char *buf); 391 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev); 392 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht, 393 int dd_data_size, 394 bool xmit_can_sleep); 395 extern void iscsi_host_remove(struct Scsi_Host *shost); 396 extern void iscsi_host_free(struct Scsi_Host *shost); 397 extern int iscsi_target_alloc(struct scsi_target *starget); 398 extern int iscsi_host_get_max_scsi_cmds(struct Scsi_Host *shost, 399 uint16_t requested_cmds_max); 400 401 /* 402 * session management 403 */ 404 extern struct iscsi_cls_session * 405 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost, 406 uint16_t, int, int, uint32_t, unsigned int); 407 extern void iscsi_session_teardown(struct iscsi_cls_session *); 408 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *); 409 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn, 410 enum iscsi_param param, char *buf, int buflen); 411 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session, 412 enum iscsi_param param, char *buf); 413 414 #define iscsi_session_printk(prefix, _sess, fmt, a...) \ 415 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a) 416 417 /* 418 * connection management 419 */ 420 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *, 421 int, uint32_t); 422 extern void iscsi_conn_teardown(struct iscsi_cls_conn *); 423 extern int iscsi_conn_start(struct iscsi_cls_conn *); 424 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int); 425 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *, 426 int); 427 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err); 428 extern void iscsi_session_failure(struct iscsi_session *session, 429 enum iscsi_err err); 430 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn, 431 enum iscsi_param param, char *buf); 432 extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr, 433 enum iscsi_param param, char *buf); 434 extern void iscsi_suspend_tx(struct iscsi_conn *conn); 435 extern void iscsi_suspend_queue(struct iscsi_conn *conn); 436 extern void iscsi_conn_queue_work(struct iscsi_conn *conn); 437 438 #define iscsi_conn_printk(prefix, _c, fmt, a...) \ 439 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \ 440 fmt, ##a) 441 442 /* 443 * pdu and task processing 444 */ 445 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *); 446 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task, 447 struct iscsi_r2t_info *r2t, 448 struct iscsi_data *hdr); 449 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *, 450 char *, uint32_t); 451 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *, 452 char *, int); 453 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *, 454 char *, int); 455 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t); 456 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t); 457 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t); 458 extern void iscsi_requeue_task(struct iscsi_task *task); 459 extern void iscsi_put_task(struct iscsi_task *task); 460 extern void __iscsi_put_task(struct iscsi_task *task); 461 extern void __iscsi_get_task(struct iscsi_task *task); 462 extern void iscsi_complete_scsi_task(struct iscsi_task *task, 463 uint32_t exp_cmdsn, uint32_t max_cmdsn); 464 465 /* 466 * generic helpers 467 */ 468 extern void iscsi_pool_free(struct iscsi_pool *); 469 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int); 470 extern int iscsi_switch_str_param(char **, char *); 471 472 /* 473 * inline functions to deal with padding. 474 */ 475 static inline unsigned int 476 iscsi_padded(unsigned int len) 477 { 478 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1); 479 } 480 481 static inline unsigned int 482 iscsi_padding(unsigned int len) 483 { 484 len &= (ISCSI_PAD_LEN - 1); 485 if (len) 486 len = ISCSI_PAD_LEN - len; 487 return len; 488 } 489 490 #endif 491