1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * iSCSI lib definitions
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
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>
24 struct scsi_transport_template;
25 struct scsi_host_template;
31 struct iscsi_transport;
32 struct iscsi_cls_session;
33 struct iscsi_cls_conn;
38 #define ISCSI_DEF_XMIT_CMDS_MAX 128 /* must be power of 2 */
39 #define ISCSI_MGMT_CMDS_MAX 15
41 #define ISCSI_DEF_CMD_PER_LUN 32
43 /* Task Mgmt states */
55 /* Connection flags */
56 #define ISCSI_CONN_FLAG_SUSPEND_TX 0
57 #define ISCSI_CONN_FLAG_SUSPEND_RX 1
58 #define ISCSI_CONN_FLAG_BOUND 2
60 #define ISCSI_ITT_MASK 0x1fff
61 #define ISCSI_TOTAL_CMDS_MAX 4096
62 /* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
63 #define ISCSI_TOTAL_CMDS_MIN 16
64 #define ISCSI_AGE_SHIFT 28
65 #define ISCSI_AGE_MASK 0xf
67 #define ISCSI_ADDRESS_BUF_LEN 64
70 /* this is the maximum possible storage for AHSs */
71 ISCSI_MAX_AHS_SIZE = sizeof(struct iscsi_ecdb_ahdr) +
72 sizeof(struct iscsi_rlength_ahdr),
73 ISCSI_DIGEST_SIZE = sizeof(__u32),
82 ISCSI_TASK_ABRT_TMF, /* aborted due to TMF */
83 ISCSI_TASK_ABRT_SESS_RECOV, /* aborted due to session recovery */
84 ISCSI_TASK_REQUEUE_SCSIQ, /* qcmd requeueing to scsi-ml */
87 struct iscsi_r2t_info {
88 __be32 ttt; /* copied from R2T */
89 __be32 exp_statsn; /* copied from R2T */
90 uint32_t data_length; /* copied from R2T */
91 uint32_t data_offset; /* copied from R2T */
92 int data_count; /* DATA-Out payload progress */
94 /* LLDs should set/update these values */
95 int sent; /* R2T sequence progress */
100 * Because LLDs allocate their hdr differently, this is a pointer
101 * and length to that storage. It must be setup at session
104 struct iscsi_hdr *hdr;
105 unsigned short hdr_max;
106 unsigned short hdr_len; /* accumulated size of hdr used */
107 /* copied values in case we need to send tmfs */
112 int itt; /* this ITT */
114 unsigned imm_count; /* imm-data (bytes) */
115 /* offset in unsolicited stream (bytes); */
116 struct iscsi_r2t_info unsol_r2t;
117 char *data; /* mgmt payload */
119 struct scsi_cmnd *sc; /* associated SCSI cmd*/
120 struct iscsi_conn *conn; /* used connection */
122 /* data processing tracking */
123 unsigned long last_xfer;
124 unsigned long last_timeout;
125 bool have_checked_conn;
127 /* T10 protection information */
130 /* state set/tested under session->lock */
133 struct list_head running; /* running cmd list */
134 void *dd_data; /* driver/transport data */
137 /* invalid scsi_task pointer */
138 #define INVALID_SCSI_TASK (struct iscsi_task *)-1l
140 static inline int iscsi_task_has_unsol_data(struct iscsi_task *task)
142 return task->unsol_r2t.data_length > task->unsol_r2t.sent;
145 static inline void* iscsi_next_hdr(struct iscsi_task *task)
147 return (void*)task->hdr + task->hdr_len;
150 static inline bool iscsi_task_is_completed(struct iscsi_task *task)
152 return task->state == ISCSI_TASK_COMPLETED ||
153 task->state == ISCSI_TASK_ABRT_TMF ||
154 task->state == ISCSI_TASK_ABRT_SESS_RECOV;
157 /* Connection's states */
159 ISCSI_CONN_INITIAL_STAGE,
162 ISCSI_CONN_CLEANUP_WAIT,
166 struct iscsi_cls_conn *cls_conn; /* ptr to class connection */
167 void *dd_data; /* iscsi_transport data */
168 struct iscsi_session *session; /* parent session */
170 * conn_stop() flag: stop to recover, stop to terminate
173 struct timer_list transport_timer;
174 unsigned long last_recv;
175 unsigned long last_ping;
178 struct iscsi_task *ping_task;
180 /* iSCSI connection-wide sequencing */
186 int c_stage; /* connection state */
188 * Preallocated buffer for pdus that have data but do not
189 * originate from scsi-ml. We never have two pdus using the
190 * buffer at the same time. It is only allocated to
191 * the default max recv size because the pdus we support
192 * should always fit in this buffer
195 struct iscsi_task *login_task; /* mtask used for login/text */
196 struct iscsi_task *task; /* xmit task in progress */
199 /* items must be added/deleted under frwd lock */
200 struct list_head mgmtqueue; /* mgmt (control) xmit queue */
201 struct list_head cmdqueue; /* data-path cmd queue */
202 struct list_head requeue; /* tasks needing another run */
203 struct work_struct xmitwork; /* per-conn. xmit workqueue */
205 struct work_struct recvwork;
206 unsigned long flags; /* ISCSI_CONN_FLAGs */
208 /* negotiated params */
209 unsigned max_recv_dlength; /* initiator_max_recv_dsl*/
210 unsigned max_xmit_dlength; /* target_max_recv_dsl */
215 /* values userspace uses to id a conn */
217 char *persistent_address;
219 unsigned max_segment_size;
220 unsigned tcp_xmit_wsf;
221 unsigned tcp_recv_wsf;
222 uint16_t keepalive_tmo;
224 uint8_t tcp_timestamp_stat;
225 uint8_t tcp_nagle_disable;
226 uint8_t tcp_wsf_disable;
227 uint8_t tcp_timer_scale;
228 uint8_t tcp_timestamp_en;
229 uint8_t fragment_disable;
231 uint8_t ipv6_traffic_class;
232 uint8_t ipv6_flow_label;
233 uint8_t is_fw_assigned_ipv6;
237 uint64_t txdata_octets;
238 uint64_t rxdata_octets;
239 uint32_t scsicmd_pdus_cnt;
240 uint32_t dataout_pdus_cnt;
241 uint32_t scsirsp_pdus_cnt;
242 uint32_t datain_pdus_cnt;
243 uint32_t r2t_pdus_cnt;
244 uint32_t tmfcmd_pdus_cnt;
245 int32_t tmfrsp_pdus_cnt;
247 /* custom statistics */
248 uint32_t eh_abort_cnt;
249 uint32_t fmr_unalign_cnt;
253 struct kfifo queue; /* FIFO Queue */
254 void **pool; /* Pool of elements */
255 int max; /* Max number of elements */
258 /* Session's states */
260 ISCSI_STATE_FREE = 1,
261 ISCSI_STATE_LOGGED_IN,
263 ISCSI_STATE_TERMINATE,
264 ISCSI_STATE_IN_RECOVERY,
265 ISCSI_STATE_RECOVERY_FAILED,
266 ISCSI_STATE_LOGGING_OUT,
269 struct iscsi_session {
270 struct iscsi_cls_session *cls_session;
272 * Syncs up the scsi eh thread with the iscsi eh thread when sending
273 * task management functions. This must be taken before the session
276 struct mutex eh_mutex;
278 wait_queue_head_t ehwait; /* used in eh_abort() */
279 struct iscsi_tm tmhdr;
280 struct timer_list tmf_timer;
281 int tmf_state; /* see TMF_INITIAL, etc.*/
282 struct iscsi_task *running_aborted_task;
284 /* iSCSI session-wide sequencing */
289 /* This tracks the reqs queued into the initiator */
290 uint32_t queued_cmdsn;
294 int lu_reset_timeout;
295 int tgt_reset_timeout;
297 unsigned short max_r2t;
299 unsigned first_burst;
304 int dataseq_inorder_en;
320 char *discovery_parent_type;
321 uint16_t discovery_parent_idx;
322 uint16_t def_taskmgmt_tmo;
324 uint8_t auto_snd_tgt_disable;
325 uint8_t discovery_sess;
326 uint8_t chap_auth_en;
327 uint8_t discovery_logout_en;
328 uint8_t bidi_chap_en;
329 uint8_t discovery_auth_optional;
330 uint8_t isid[ISID_SIZE];
333 struct iscsi_transport *tt;
334 struct Scsi_Host *host;
335 struct iscsi_conn *leadconn; /* leading connection */
336 /* Between the forward and the backward locks exists a strict locking
337 * hierarchy. The mutual exclusion zone protected by the forward lock
338 * can enclose the mutual exclusion zone protected by the backward lock
339 * but not vice versa.
341 spinlock_t frwd_lock; /* protects session state, *
342 * cmdsn, queued_cmdsn *
343 * session resources: *
344 * - cmdpool kfifo_out , *
345 * - mgmtpool, queues */
346 spinlock_t back_lock; /* protects cmdsn_exp *
348 * cmdpool kfifo_in */
349 int state; /* session state */
350 int age; /* counts session re-opens */
352 int scsi_cmds_max; /* max scsi commands */
353 int cmds_max; /* size of cmds array */
354 struct iscsi_task **cmds; /* Original Cmds arr */
355 struct iscsi_pool cmdpool; /* PDU's pool */
356 void *dd_data; /* LLD private data */
366 /* hw address or netdev iscsi connection is bound to */
370 wait_queue_head_t session_removal_wq;
371 /* protects sessions and state */
376 struct workqueue_struct *workq;
383 extern int iscsi_eh_abort(struct scsi_cmnd *sc);
384 extern int iscsi_eh_recover_target(struct scsi_cmnd *sc);
385 extern int iscsi_eh_session_reset(struct scsi_cmnd *sc);
386 extern int iscsi_eh_device_reset(struct scsi_cmnd *sc);
387 extern int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc);
388 extern enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc);
391 * iSCSI host helpers.
393 #define iscsi_host_priv(_shost) \
394 (shost_priv(_shost) + sizeof(struct iscsi_host))
396 extern int iscsi_host_set_param(struct Scsi_Host *shost,
397 enum iscsi_host_param param, char *buf,
399 extern int iscsi_host_get_param(struct Scsi_Host *shost,
400 enum iscsi_host_param param, char *buf);
401 extern int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev);
402 extern struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
404 bool xmit_can_sleep);
405 extern void iscsi_host_remove(struct Scsi_Host *shost, bool is_shutdown);
406 extern void iscsi_host_free(struct Scsi_Host *shost);
407 extern int iscsi_target_alloc(struct scsi_target *starget);
408 extern int iscsi_host_get_max_scsi_cmds(struct Scsi_Host *shost,
409 uint16_t requested_cmds_max);
414 extern struct iscsi_cls_session *
415 iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost,
416 uint16_t, int, int, uint32_t, unsigned int);
417 void iscsi_session_remove(struct iscsi_cls_session *cls_session);
418 void iscsi_session_free(struct iscsi_cls_session *cls_session);
419 extern void iscsi_session_teardown(struct iscsi_cls_session *);
420 extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *);
421 extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn,
422 enum iscsi_param param, char *buf, int buflen);
423 extern int iscsi_session_get_param(struct iscsi_cls_session *cls_session,
424 enum iscsi_param param, char *buf);
426 #define iscsi_session_printk(prefix, _sess, fmt, a...) \
427 iscsi_cls_session_printk(prefix, _sess->cls_session, fmt, ##a)
430 * connection management
432 extern struct iscsi_cls_conn *iscsi_conn_setup(struct iscsi_cls_session *,
434 extern void iscsi_conn_teardown(struct iscsi_cls_conn *);
435 extern int iscsi_conn_start(struct iscsi_cls_conn *);
436 extern void iscsi_conn_stop(struct iscsi_cls_conn *, int);
437 extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *,
439 extern void iscsi_conn_unbind(struct iscsi_cls_conn *cls_conn, bool is_active);
440 extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err);
441 extern void iscsi_session_failure(struct iscsi_session *session,
443 extern int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn,
444 enum iscsi_param param, char *buf);
445 extern int iscsi_conn_get_addr_param(struct sockaddr_storage *addr,
446 enum iscsi_param param, char *buf);
447 extern void iscsi_suspend_tx(struct iscsi_conn *conn);
448 extern void iscsi_suspend_rx(struct iscsi_conn *conn);
449 extern void iscsi_suspend_queue(struct iscsi_conn *conn);
450 extern void iscsi_conn_queue_xmit(struct iscsi_conn *conn);
451 extern void iscsi_conn_queue_recv(struct iscsi_conn *conn);
453 #define iscsi_conn_printk(prefix, _c, fmt, a...) \
454 iscsi_cls_conn_printk(prefix, ((struct iscsi_conn *)_c)->cls_conn, \
458 * pdu and task processing
460 extern void iscsi_update_cmdsn(struct iscsi_session *, struct iscsi_nopin *);
461 extern void iscsi_prep_data_out_pdu(struct iscsi_task *task,
462 struct iscsi_r2t_info *r2t,
463 struct iscsi_data *hdr);
464 extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *,
466 extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
468 extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *,
470 extern int iscsi_verify_itt(struct iscsi_conn *, itt_t);
471 extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t);
472 extern struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *, itt_t);
473 extern void iscsi_requeue_task(struct iscsi_task *task);
474 extern void iscsi_put_task(struct iscsi_task *task);
475 extern void __iscsi_put_task(struct iscsi_task *task);
476 extern void __iscsi_get_task(struct iscsi_task *task);
477 extern void iscsi_complete_scsi_task(struct iscsi_task *task,
478 uint32_t exp_cmdsn, uint32_t max_cmdsn);
483 extern void iscsi_pool_free(struct iscsi_pool *);
484 extern int iscsi_pool_init(struct iscsi_pool *, int, void ***, int);
485 extern int iscsi_switch_str_param(char **, char *);
488 * inline functions to deal with padding.
490 static inline unsigned int
491 iscsi_padded(unsigned int len)
493 return (len + ISCSI_PAD_LEN - 1) & ~(ISCSI_PAD_LEN - 1);
496 static inline unsigned int
497 iscsi_padding(unsigned int len)
499 len &= (ISCSI_PAD_LEN - 1);
501 len = ISCSI_PAD_LEN - len;